The same way there were and there are people complaining about things in this arc
Even if the focus of the arc was mainly Zoro, which could never be, because Luffy always gets the most, especially in an arc that had the whole post-ts as a build up and its supposed to be a war, which is Wano, all that shit would be the same
You think all Zoro fans liked all the Enma stuff? The Shimotsuki stuff? The Zoro, Orochi and Hyiori stuff? The Mink Elixir thing? Zoro and Sanji being called "wings of the Pirate King" and fighting together? ZKK not happening after dudes insult their moms for not believing on it?
Its normal to try to hype up your fave, especially if they are the ones who get the most shine after the main protagonist, but try to convince someone that Zoro is going to kill Kaido and that One Piece is Vagabond 2.0 and then act like it is all good, like it was all about everyone hating Zoro or his fans for no reason or something, this is bs
The real Zoro haters might have understimated Zoro, just like Sanji haters did, theres no big deal about it
And besides, OP has a very slow build up, Oda sets up things now to be resolved in years to come.
"No one said shit to Sanji fans in wci"
wut?

Guys do that on Wano, why wouldn't they do it in WCI?