Hahhahahahaha so it is ok for Kid to have ''Luffy's back'' for BM but god forbid Zoro to do it for Kaido

It is true that Luffy ''keeps his word'' most of the time but it happens that he doesn't and you even gave Kid's example so why deny it to Zoro ?
Nah read the OP, it's not about ZKK not happening. I actually like the idea. It does actually make sense from a logical standpoint. The problem is I'm a skeptic to Oda hyping something "different" before not doing it.
It's about Oda committing values he normally has about "main" (key word) OP villains that Luffy fights.
Kid "defeating" Big Mom (who btw, never has been a main villain. Katakuri and Kaido take that role in WCI/Wano respecttively), either by permanently making her O-Lin or anything else, is okay because Luffy effectively "won" against the BMP last arc.
This is the big reason Morgans writes his article about Luffy. He says he's the 5th emperor because he made her "lose" (she gets pissed at the article, remember). At this point BM in relation to Luffy trying to prove something to her is meaningless.
Plus, if Kaido and Linlin are "equal" and Luffy defeats Kaido, it effectively means he can or could have defeated Linlin. Yes, I hope ZKK happens where it fits the mold of the story.
Where I was actually making fun of ZKK is not the actual act of it, but the notion that some supporters of it think Zoro will overtake Luffy's 1v1 at some point (look at the OP where I reference it, it's about the actual 1v1, not what happens after). Reasonable members here of course don't believe that, and think Zoro will have relevance down below, learn his history with wano, improve CoC, then at the absolute end of the arc when Kaido is defeated by recovers, will pull the Ryuuma moment.
THAT I fundamentally agree with. I'm just nervous for Oda's....tendencies to not commit.