you can't ban edge camping, but you CAN ban using edgecamping to stall a match, if there is a way to do it and remain invincible.
Bet just to stimulate meaningful discussion, let's look at what IS banned in smash games:
items, for the most part:
This isn't for any "overbalanced issues, but rather they lessen the competative nature of the game by introducing an element of luck
infinite stalling
This would be primarily jiggz, rising pound, but includes wall bombing, luigi infinate, or any of those. Even though the chars themself aren't banned, not using the moves mentioned, the application is banned, because it stalls the game indefinitely, and as tourney matches have a time limit, can lead to getting a slight % lead and simply remaining out of possible reach for the opponent. This made jigglypuff unbeatable, unless you picked up the puff yourself, in an effort to stop his stalling.
wobbling/red shell glitch/IC ice glitch:
These rendered the opponent immobile. Although wobbling was situational, it some places it was banned because it allowed unescapable 0-death combos. The freeze glitch/red shell glitch was banned because it also prevented the opponent from moving, and thus made the characters overpowered unless you played a ditto match, where you had equal opportunity to do the same back.
So now let's look at metaknight. He has no 0-death combos, nor means as to immobalize the opponent. He can't infinite stall, nor can he otherwise stall the match. However, there is ONE aspect that, depending on the final decision of the community, makes him match the other banned items:
The fact that many people are picking up MK just to fight another MK, along with the possibility of him limiting the competative nature of the game (as items did, though by a different reason).
However, as many have pointed out, because of MK's inherent advantages, people seem to favor picking him rather than sticking with and advancing the Metagame of other characters; perhaps because there is in fact no better way to beat him than play him.
Anyways, I'm not giving my opinion, as I've stated it before, as I'm not good enough to have it be heard, but what I'm saying is that MK shares something in common with previous bans, but does NOT share the primary reason they're banned, namely that he puts the opponent at such an advantage that the game is totally unwinnable....