Yeah, but apart from wanting this to happen, is there good reason to think it will happen. I'm not trying to understand why you don't want Zoro to face Kaido as his main opponent, I'm trying to understand why you don't think he will.
My God, the build up for Zoro battle with Kaido is very extensive. Neither Zoro or King even acknowledged the other's existence, and they were on the same floor for 10 chapters. Zoro has much more buildup with Queen.
I'm not trying to deny the buildup to Zoro cutting Kaido or his parallels to Oden, at this point anyone who isn't a blind hater or troll would expect all that buildup to culminate in Zoro performing a big feat against Kaido at some point, it is undeniable.
But ultimately, Kaido is the main antagonist of the arc, of the whole saga we've been building up to since Punk Hazard, the main emotional conflict and barrier to overcome, with many characters wanting his head or revenge on him. His defeat would symbolise the liberation of Wano, the release from all the pain it's citizens have gone through. If Kaido is in fact defeated here, then Luffy is the one who should defeat him, it is his role in the story. The scabbards, Yamato, Otama and Wano in general have put his hopes on him, and him and Kaido simply have had way more buildup to their fight.
So if i personally believe there's no way Zoro is the one to defeat/kill Kaido, then the next best thing is for him to play a part on his downfall, which i think everyone here agrees WILL happen. The whole point of this topic is to convince people that Kaido will be his "main" fight, and if that means damaging him but ultimately not defeating him, then sure, that could be his "main" fight.
But why can't he can do that, and then also have a duel with King simply for the sake of getting a 1v1 fight this arc? I don't think there needs to be any buildup. If a strong opponent stands in the way of the straw hats and Luffy is too busy to handle it, then Zoro will step up to the plate. Mr.1, Ohm, Kaku and such didn't have any real buildup or particular conflict with Zoro and only revealed some sort of ability that Zoro would need to challenge himself to overcome during the fight itself. Assuming that Zoro is already too strong for King is just feeding into our nebulous idea of the power levels of the series, if Oda has an interesting scenario for the fight then it can happen.
Again it all depends on how the climax is actually handled. Is this the actual final battle?; Can Marco and the others down there handle/defeat the calamities?; Will Big Mom be defeated this arc or betray Kaido?
If the location of the final battle were to shift up to somewhere like Kozuki castle and King acted as a sort of final guard leading to Kaido, then Zoro would fight him, it is as simple as that.