People won't stop complaining. Everybody wants to have a character in smash, and in a perfect world nobody would complain because the character they want is already in, but the poor devs only have so much time and space to add characters, so people are obviously going to be talking about who they hope makes it in. Personally, I do find it annoying constantly talking about the same character everywhere, especially geno and waluigi (waluigi isn't getting in pls stop), but everybody wants a character, and I constantly talk about wanting Isaac in so I'm too blame for the problem too.

tl;dr: everybody wants to see their favorite characters represented in smash, but not everybody's going to get what they want. People have the right to speak out about what characters they want.