I dunno about you, but Steve getting added in means nothing about Banjo v Steve. If anything it means that both sides got what they wanted yes? Certainly better than only having one or none of them. Even then I find the idea of character v character debates stupid in the first place. If Sakurai or Nintendo wants a specific character(going by Sakurai's comment it was Nintendo's choice this time) they'll try to get it. If not.. well what else can they do? The fanbase has nothing to with that process, and frankly debating over 2 seperate characters chances is overall pointless.
Also, where are you getting the idea that Sakurai didn't want to do Steve? He was forced to sure, and he had to redesign every single stage in the game(so around 100+) just to make Steve's gimmick work, but A) that's his job and B) nothing he directly said seemed to say anything about him hating it. If anything, I think it's the inverse. But I don't have any definite proof either way ¯\(ツ)/¯ unless that one twitter account that people called fake was actually Sakurai. just don't think he straight up hated working on it.