Powerlevel
Zoro right now, in my opinion, is on YC1 level, he might be slightly above King and Katakuri right now, but still in YC1 range and far away of an Yonko. We see the big difference between YC1 und Yonko by comparison of Katakuri and Kaido, specially when we consider how much Power Ups Luffy already needed to fight Kaido. So i cant imagine to kill Kaido would be in any form honourable for Zoro or anyone, if he is (way) stronger than Zoro.
Zoro right now, in my opinion, is on YC1 level, he might be slightly above King and Katakuri right now, but still in YC1 range and far away of an Yonko. We see the big difference between YC1 und Yonko by comparison of Katakuri and Kaido, specially when we consider how much Power Ups Luffy already needed to fight Kaido. So i cant imagine to kill Kaido would be in any form honourable for Zoro or anyone, if he is (way) stronger than Zoro.
So, if you scale him correctly, there is no issue.
Luffy takes always the W
Luffy has always been the one taking down the final opponent, specially in a whole arc. He is also fighting Kaido so long and giving that final blow after to Zoro, just makes no sense to me. Zoro had his big opponent and even if i would claim Zoro to be way stronger then King, i know he had his fight already, while Luffy is in his. After all, Luffy is the MC and will take the main credit, doesn’t matter how much we like Zoro, Sanji, Kid, Law etc..
Luffy has always been the one taking down the final opponent, specially in a whole arc. He is also fighting Kaido so long and giving that final blow after to Zoro, just makes no sense to me. Zoro had his big opponent and even if i would claim Zoro to be way stronger then King, i know he had his fight already, while Luffy is in his. After all, Luffy is the MC and will take the main credit, doesn’t matter how much we like Zoro, Sanji, Kid, Law etc..
Luffy isnt the one who always takes down the final opponent - Zoro literally took out the main villain in his introduction and protected the crew from the biggest threat in Thriller Bark.
Giving Zoro the final blow on Kaido makes perfect sense because the victor of Luffy vs Kaido has already been declared Kaido.
Zoro already had his fight? This is not the first time for Zoro to have multiple fights. He ran a gauntlet in several arcs.
Credit can go to Luffy all the same, after all, it's his crew member who killed Kaido.
Luffy grew so much already...
In this arc, Luffy got already alot of powerups, from advCoA, CoC, fighting style over all, stamina and finally his awakening. He grew so much to get on Kaidos level to beat him, just to have him being overshadowed after that, by Zoro who got his own upgrades, which was used to beat King. Giving the vice-captain suddenly another upgrade to push him above the MC, which got a HUUUUGEEE powerup now just seems to be wrong, storywise.
In this arc, Luffy got already alot of powerups, from advCoA, CoC, fighting style over all, stamina and finally his awakening. He grew so much to get on Kaidos level to beat him, just to have him being overshadowed after that, by Zoro who got his own upgrades, which was used to beat King. Giving the vice-captain suddenly another upgrade to push him above the MC, which got a HUUUUGEEE powerup now just seems to be wrong, storywise.
And still, he is fighting an exhausted Kaido, not a fresh one.
Zoro was already strong the whole time, he doesnt need much growth.
If you accept the possibility of Oda wanting Zoro as #1 of the universe, it's not wrong at all, storywise.
Out of Character / Loyality
A very big point in my point of view is Zoros character. He is loyal to Luffy, above everything. He gave away his pride to get stronger for Luffy (his claim to Mihawk), he was ready to give everything and even die for Luffy and he respects him as captain. When Luffy wins his fight or claims this is his fight, Zoro wont interfere. And when Luffy already won and decided to let Kaido live (what he always do with his opponents), Zoro would never ignore the decision of his captain and act against this (indirect) orders. Loyality is a big point for Zoro (look at the Sanji-Situation, or the Usopp-Situation), so there is no way, in my opinion, where he throws away his loyality to gather something unhonorable like killing some already beaten enemy.
A very big point in my point of view is Zoros character. He is loyal to Luffy, above everything. He gave away his pride to get stronger for Luffy (his claim to Mihawk), he was ready to give everything and even die for Luffy and he respects him as captain. When Luffy wins his fight or claims this is his fight, Zoro wont interfere. And when Luffy already won and decided to let Kaido live (what he always do with his opponents), Zoro would never ignore the decision of his captain and act against this (indirect) orders. Loyality is a big point for Zoro (look at the Sanji-Situation, or the Usopp-Situation), so there is no way, in my opinion, where he throws away his loyality to gather something unhonorable like killing some already beaten enemy.
Zoro does what's necessary and what Luffy cant do. He steps in when Luffy lacks.
Kaido wont be beaten when Zoro returns, Kaido is obviously gonna be fighting after Luffy encounter.
ZKK-Fandom...
Its sad that this is an argument already, but it is. If you state somewhere you don’t like the idea or you argue against it, you will get instantly some insults or claims how stupid your argumentation is or how biased you are. A few really argue with you and disagree, which is fine, but the majority just goes to troll you completely, just because you disagree. This point mainly makes me hate the theory. Not because of the theory itself, but because of the fandom putting this on the table on every damn thread. I understand the Zoro fandom like the theory and discussing it is fine and cool, but it got damn out of the hand and if every second thread is about ZKK in some way, its not fun anymore. Specially when another good theories just get lost. Overall, i would love to see more theories and great theorie-threads about different topics.
Its sad that this is an argument already, but it is. If you state somewhere you don’t like the idea or you argue against it, you will get instantly some insults or claims how stupid your argumentation is or how biased you are. A few really argue with you and disagree, which is fine, but the majority just goes to troll you completely, just because you disagree. This point mainly makes me hate the theory. Not because of the theory itself, but because of the fandom putting this on the table on every damn thread. I understand the Zoro fandom like the theory and discussing it is fine and cool, but it got damn out of the hand and if every second thread is about ZKK in some way, its not fun anymore. Specially when another good theories just get lost. Overall, i would love to see more theories and great theorie-threads about different topics.
Most people who talk about ZKK are those who oppose it, you can see each week threads popping up about how ZKK aint happening.
Those who oppose it are deep down knowing it is very likely happening and they are starting to lose their mind realizing that they are the ones who are the true laughing stock of the last 4 years. Blaming ZKK fandom is the only way for them to cope with possible future.