They should just remove Wavedashing entirely, its nothing but an unfair glitch that competitive players abuse in order to win matches. It takes no skill to use and it is extremely broken and op. If you ask me, this game would be a lot better if they just deleted wavecheating altogether.
This is the wrong thread to say that kind of thing. But I'll say a few things:
1) Not a glitch, just not foreseen how it would be used. It's a corner case of physics - Sakurai noticed this happened, but didn't realize it had applications for pretty much every character.
2) It takes skill to use - I can't do it except for wavelanding onstage and very very sporadic wavedashes mid-match (and that's why I'm a janky-as-all-get-out Falco, but I can L-cancel enough and try to trick opponents to sometimes take sets off players who are more technically skilled than I).
3) Go play Brawl, Brawl-, Balanced Brawl, or another mod - they don't have wavedashing (Brawl- Fox can, but it's one character), and from my experience they are all still great games to play. If you don't like PM, just don't play it, but also don't go spreading objectionable opinions or Melee/PM hate here. The Brawl boards don't like stuff like this [who by and large deal with the bulk of the X Smash game hate] and I would assume the PM boards don't want it either.
4) They'd need to redesign several characters for this - for example, Luigi would go from being ok to being one of the worst characters, with terrible air speed, bad dash speed, and no way to punish out of shield because he slides too far.
5) They'd also have to redesign airdodging entirely - no directional boost, or once per airtime, or like Brawl, or like Smash 4 (Extra landlag) - it's not exactly a simple task.
I'd ask other people not to respond to this and/or flame him, since that will just make the thread spiral in a way that's unproductive.