Waluigi was a character essentially made so that Wario might have an accomplice in Mario Tennis 64. He is presumably not considered as high need as even Luigi or Peach. The way that he is a help prize like numerous different characters features which priority section he is in: unquestionably a conspicuous character, yet insufficient to be a playable character.
He was designed to be a loser character who is never made to succeed at the end day. Dominating matches in crush siblings would invalidate the point of his creation. This is additionally one reason why he never had his own game. He was not there or made to win and he never won.
In short generally Nintendo fans, Smash fans simply dont care less if he’s in crush or not, just Waluigi fans care. What fans are eager is to see more warriors being added in to the game.
Waluigi isn’t like anybody in the Smash games. What’s more, he’s just ever been in Mario side projects, so that is possibly why he’ll won’t be in Smash Bros. In any case, perhaps his opportunity will come sometime in the future. Waluigi is now a help prize, and he functions admirably as one as well, so that may be a motivation behind why.