So this chapter proves me right and wrong at the same time. My opinion has been that current luffy is actually just dogshit, because of g5 limit that many ppl seem to be ignoring (luffy just has to bajrang gun!, as if admirals have to face that attack in a 1v1) , and just because he managed to finish lucci off in time, does not mean he'd finish off a top tier before g5 runs out and he becomes defenceless, and from there he dies easily.
What this chapter shows is, that luffy can in fact damage a top tier enough, to the point that even if G5 runs out, the top tier is physically incapable of getting up and finishing the fight there and then, which actually gives luffy enough time to recover.
If he can do it to Kizaru, he can do it to greenbull, he can do it to aokiji as well and this is why I don't think Kizaru stocks actually fall that far down, depends how you look at it. Aokiji got hit by garp who was right in front of him, because he didn't expect the attack since they were having dialogue and the fight hadn't actually started yet.
In this case luffys attack was unexpected because he was spinning around being an idiot, which actually helped to mask the attack that Kizaru didn't expect, and so was not able to react to it on time.
This shows if the opponent is fast enough they can catch an admiral off guard and do notable damage, and they cant just "morph" the attacks, or kizaru can't just "avoid it because he's faster" . I could make an argument for that with marco hitting aokiji at MF for example, but many people don't take MF seriously in that regard, but I don't need to anyway.
This doesn't actually change my opinion all too much, I just think that it went from Kizaru winning 10/10 times vs Luffy in a 1v1, to 9/10, because lets be honest, the 1/10 chance happened in this chapter for the sake of plot, otherwise nothing was stopping Kizaru if he'd blocked the attack, from lasering luffy through the heart a million times with the state he's in. But at the end of the day it still happened plot or not, this boosts Luffy up for me.
I think Mihawk and Shanks still easily beat luffy, because I don't even think shanks or mihawk would get hit by that attack, nor the attacks from garp. The admirals don't even have time to use the FS they may or may not have in time, whether its because they just don't opt to, or not or literally just can't, don't really matter, the whole obs haki thing is inconsistent anyway.