But that's the thing. We'd be banning stuff to make it "More fair" due to an arbitrary view on what constitutes "fair".
What's next, removing certain counterpicks for just being too good for some characters (as opposed to stages that are just broken)? Banning more than MK if another (or several) character rises up to the same level (
if)? Arbitrary limits on chaingrabs and locks and whatnot?
I mean, if we wanted to optimize Compeitiveness, fairness and limit suckiness, we'd start putting arbitrary limits on everything. F-tilt locks (Sheik) must be limited to X number of F-tilts, Zamus' Dsmash Lock must be limited to X number of Dsmashes. Chaingrabs must be limited to a number of grabs (dependant on which chaingrab we're talking about), etc., etc., etc.
If we're not banning things for just being "too good" but instead doing it simply because we feel like it in order to make the game less sucky, we might as well cave in and hack the game as well to make it some kind of balanced monster a la GG.
The point of bringing up other communities is to show that, no, a character having no bad matchups doesn't automatically destroy the metagame, unless every other community in existence for some reason just elects not to be drawn to those characters for some random reason. No, those communities' players just get good enough to be able to win tournaments with other characters, some with bad to horrible matchups against that fabled "No Bads" character.
The only reason why there are so many MKs ATM is out of
choice. The Smash community is just to set to win and lazy that people just run off to "The Best" if there's a clear "The Best". It's not because MK's so good they have to switch, they just want the easy way out.