Some thoughts about Luffy and Zoro
•Zoro's Ashura is going to leave a scar (the second after Oden), his attack potency is on another level. Actually the whole guy is on another level. I also suspect that this wound may effect Kaido later, during his fight with Luffy. Another tremendous feat for Zoro, I don't know what there is actually there to downplay here. Zoro fans have been eating beyond well in Wano and Zoro's role isn't finished yet, I can assure you.
•Luffy is the GOAT. His haki bloomed and he started applying this CoC version. Even base Luffy right now is wildy impressive, let alone when he is going to use things like gear 4 etc. In this fight he will trade blows on relative terms with Kaido, at least for some time.
This is how I see things playing out : leaving aside an X factor like Yamato, I think that Luffy is going to have his 1 vs 1 against Kaido for several chapters. In the meanwhile, Zoro will be downstairs to mostly recover though Oda might very well give him something else to do (and given his conditions, I doubt that it will be fighting someone).
When Luffy will beat Kaido (mantaining his portrayal and what has been built up for hundreds of chapters about him defeating Kaido) they will both be very exhausted but the Zoan recovery will partially kick in and Kaido will go in his dragon form and fly. That's when, under the eyes of the Flower Capital, in the chapter that bears his name, Zoro will slay him with Hiryu Kaean (the one hit that previously missed him, foreshadowing that it will eventually hit him) beheading him. This will also mantaing the portrayal and buildup/foreshadowing for Zoro being the one to kill him (which I am not going to talk about because it would be too long) and will mirror the Ryuma legend, with Wano finally beeing freed from the demon.
Luffy fans and Zoro fans shoudn't really be arguing about this rooftop fight. For what regards Zoro, Oda gave him tremedous hype (with his rooftop overall performance) and character moments (his spirit of self sacrifice that has always been part of him, especially when it comes to defending his captain, which he did multiple times in this fight). He emphasized so much this character trait of Zoro that he even made him jump without any hesitation against an island level attack from two emperors, receiveing great damage in return.
Luffy also received tremendous hype as the man who will become PK, that will that is impossible to break, the man who is supposed to accomplish the impossible. His haki bloomed as well. Oda also once again focused on the notion that having certain people on his side (Zoro in this case) is just as important as being who Luffy is. Zoro saved him multiple times and now Luffy will repay everyone by saving them in return, like he always does.
This was a great execution by Oda of many of the things that make us apprecciate Luffy and Zoro.