So it is a common thing when debating the story and specially when power scalling for people to come up with the "he was holding back" argument to justify a certain character (usually his favorite) looking bad or not that good in some situations.
I thing the first example of this would be Marineford where Admiral fans stated that marines were holding back to not destroy Marineford since it was the "home"(?) of a lot of marines and therefore they couldn't let that place being destroyed. And they use the example of Aokiji vs Akainu 10 days fight at Punk Hazard as a result of what Marineford would've become if they went all out. Although I could agree some aspects of marines not going all out from beginning I don't think when Kizaru, Aokiji, Akainu were truly fighting that they were being careful about not destroying Marineford. Specially after reading this line of their commander Sengoku:
When Teach said he would sink Marineford that's when Sengoku truly engaged on fighting saying he wouldn't allow that to happen saying that the Fortress could be rebuild but if the Island was gone that would cause a huge impact to the people of the world who trust on marines and fear pirates. So destroying Marineford was never an issue as long it doesn't sink. And Akainu and Aokiji fighting all out with each other wasn't able to sink Punk Hazard. Probably just Whitebeard's DF is able to such thing. And now Mother Flames too.
The other case would'be the recent Egghead arc where Kizaru was giving a mission that went in conflict with his feelings. Although Kizaru succesfully managed all the orders he was giving to at the end of the arc we could see how devasted he became about doing all that:
(By the way didn't realized before that Akainu called him brother. Are they truly brothers or just close friends?)
Giving Kizaru's natural troll tone through the series and sunglasses we couldn't be sure till this panel if he was affected by all that situation or not. But even with that said we can't be sure about that affecting his fighting capabilities since only at the end of the arc he let his emotions going out.
So this is coming about probably the biggest fan of Kizaru (alone not all Admirals) that puts him as top 1 of the verse simply because of his DF.In Marineford there doesn't seem to have any reason to justify him being holding back. In Egghead there is an argument to be made why he is SUBCONSCIOUSLY holding back but we can't be sure since at the end he still do what it is needed to. Oh and of course let's not forget the feeding Luffy plot...
After fighting with Kizaru and hitting him in the head making him incapable of fighting for sometime while he himself was at the limit of his G5 transformation also unable to fight for sometime (and in need of some food) somehow someone delivers him a lot of food to allow him to recover and a big theory is that Kizaru conflicted about himself was the one responsible for this hoping Luffy could save Vegapunk from him and Saturn. But there are many issues with that theory the first one being that Kizaru still tried hard to kill Vegapunk after that and succeeded (his aim was always the main body not the other ones). And the other issue is the right next page after that one of Luffy getting feed:
Kizaru is shown still visible "drunk" after receiving Luffy's last attack in the head. Like he had a knocked down if they were fighting in a boxing ring and the judge was counting to 10. So it is very unlikely that Kizaru would be able to do that even giving his light speed because of his condition and even doing it without Saturn, who most likely has CoO, noticing. Instead there is a much more likely possibility that holds coheresion that people don't talk about (or at least I don't remember seeing anyone talking about it) that would be this:
Van Augur having the teleportation Devil Fruit would fits here much better than Kizaru that despite his light speed people would still see a bright light deliverying food to Luffy. We don't know exactly what the blackbeard pirates mission was but is easy to assume that having Luffy recovered to fight and distract marines, and specially Saturn, would surely a lot benefitial for their goal.
I think with that we could close the case of Kizaru holding back while fighting at Egghead.
Now going outside of One Piece manga we also have the most controversial fight between Gojo vs Sukuna where many claims that Sukuna was holding back because he wanted to learn how to counter Gojo's infinity and because he knew he had to save energy to fight a lot of people after Gojo.
Well first of all Sukuna never said such thing for people to assume he wanted to learn how to counter infinity before killing Gojo. If that was true it would make no sense to try to kill Gojo with his domain expasion way before that. The second guess would've make sense but still out be kind of stupid if he couldn't even defeat Gojo first just because he was holding back thinking in after fights...
And something that I just heard recently people talking and makes totally sense is that Gojo had much more reason to hold back while fighting Sukuna because he wanted to save his student Megumi. And that could've be used to justify Gojo actually being stronger.
But at the end of the day all we have are Gojo's (aka authors) own words declaring Sukuna stronger. And nothing of that bullshit holding back crap.
We can find many cases of holding back arguments in a bunch of other animes/mangas. I'd say Dragon Ball would be the biggest one giving how since the very first saga of DBZ the main characters already have the power to explode the planet if they want to and the power creep till the end of DBZ is... I don't even have words to describe it. It is fully absurd. And therefore everyone could say that Z warriors were holding back to not destroy Earth and bla bla bla.
The main point of this (probably confusing) thread is that people should stop to say characters are holding back without concret evidence inside the manga because if you don't have that the only thing you have is your own headcannon.
I thing the first example of this would be Marineford where Admiral fans stated that marines were holding back to not destroy Marineford since it was the "home"(?) of a lot of marines and therefore they couldn't let that place being destroyed. And they use the example of Aokiji vs Akainu 10 days fight at Punk Hazard as a result of what Marineford would've become if they went all out. Although I could agree some aspects of marines not going all out from beginning I don't think when Kizaru, Aokiji, Akainu were truly fighting that they were being careful about not destroying Marineford. Specially after reading this line of their commander Sengoku:

When Teach said he would sink Marineford that's when Sengoku truly engaged on fighting saying he wouldn't allow that to happen saying that the Fortress could be rebuild but if the Island was gone that would cause a huge impact to the people of the world who trust on marines and fear pirates. So destroying Marineford was never an issue as long it doesn't sink. And Akainu and Aokiji fighting all out with each other wasn't able to sink Punk Hazard. Probably just Whitebeard's DF is able to such thing. And now Mother Flames too.
The other case would'be the recent Egghead arc where Kizaru was giving a mission that went in conflict with his feelings. Although Kizaru succesfully managed all the orders he was giving to at the end of the arc we could see how devasted he became about doing all that:

(By the way didn't realized before that Akainu called him brother. Are they truly brothers or just close friends?)
Giving Kizaru's natural troll tone through the series and sunglasses we couldn't be sure till this panel if he was affected by all that situation or not. But even with that said we can't be sure about that affecting his fighting capabilities since only at the end of the arc he let his emotions going out.
So this is coming about probably the biggest fan of Kizaru (alone not all Admirals) that puts him as top 1 of the verse simply because of his DF.In Marineford there doesn't seem to have any reason to justify him being holding back. In Egghead there is an argument to be made why he is SUBCONSCIOUSLY holding back but we can't be sure since at the end he still do what it is needed to. Oh and of course let's not forget the feeding Luffy plot...

After fighting with Kizaru and hitting him in the head making him incapable of fighting for sometime while he himself was at the limit of his G5 transformation also unable to fight for sometime (and in need of some food) somehow someone delivers him a lot of food to allow him to recover and a big theory is that Kizaru conflicted about himself was the one responsible for this hoping Luffy could save Vegapunk from him and Saturn. But there are many issues with that theory the first one being that Kizaru still tried hard to kill Vegapunk after that and succeeded (his aim was always the main body not the other ones). And the other issue is the right next page after that one of Luffy getting feed:

Kizaru is shown still visible "drunk" after receiving Luffy's last attack in the head. Like he had a knocked down if they were fighting in a boxing ring and the judge was counting to 10. So it is very unlikely that Kizaru would be able to do that even giving his light speed because of his condition and even doing it without Saturn, who most likely has CoO, noticing. Instead there is a much more likely possibility that holds coheresion that people don't talk about (or at least I don't remember seeing anyone talking about it) that would be this:

Van Augur having the teleportation Devil Fruit would fits here much better than Kizaru that despite his light speed people would still see a bright light deliverying food to Luffy. We don't know exactly what the blackbeard pirates mission was but is easy to assume that having Luffy recovered to fight and distract marines, and specially Saturn, would surely a lot benefitial for their goal.
I think with that we could close the case of Kizaru holding back while fighting at Egghead.
Now going outside of One Piece manga we also have the most controversial fight between Gojo vs Sukuna where many claims that Sukuna was holding back because he wanted to learn how to counter Gojo's infinity and because he knew he had to save energy to fight a lot of people after Gojo.
Well first of all Sukuna never said such thing for people to assume he wanted to learn how to counter infinity before killing Gojo. If that was true it would make no sense to try to kill Gojo with his domain expasion way before that. The second guess would've make sense but still out be kind of stupid if he couldn't even defeat Gojo first just because he was holding back thinking in after fights...
And something that I just heard recently people talking and makes totally sense is that Gojo had much more reason to hold back while fighting Sukuna because he wanted to save his student Megumi. And that could've be used to justify Gojo actually being stronger.
But at the end of the day all we have are Gojo's (aka authors) own words declaring Sukuna stronger. And nothing of that bullshit holding back crap.
We can find many cases of holding back arguments in a bunch of other animes/mangas. I'd say Dragon Ball would be the biggest one giving how since the very first saga of DBZ the main characters already have the power to explode the planet if they want to and the power creep till the end of DBZ is... I don't even have words to describe it. It is fully absurd. And therefore everyone could say that Z warriors were holding back to not destroy Earth and bla bla bla.
The main point of this (probably confusing) thread is that people should stop to say characters are holding back without concret evidence inside the manga because if you don't have that the only thing you have is your own headcannon.