That's just wrong. Ledgecamping completely negates any players skill difference
If you're johning about Ledge Camping, pick a character who can counter it. All you need is a projectile/reflector/absorb-er/etc. Obviously, not all projectiles do the trick, but a lot of characters have the options to deal with Ledge Camping.
-Snake
-Falco
-ROB
-Pikachu
-Ice Climbers
-Pit
-Wolf
-Toon Link
-Fox
-Zelda
-Lucas
-Ness
-Samus
-Link
All of these characters have projectiles that can deal with the ledge, reflectors of some kind, or both. That's 14 out of 39 characters(Zelds counts as two, Samus counts as two, PT counts as 3. That's 4 additional characters characters, so 39 in all. 37 if you think PT should count as one, but that just raises the percentage) That's over 33% of the characters in this game.
And other characters have abilities to stop ledge camping as well, but these seem to be the best. I simply listed them by order of tiers, so Snake is not neccessarily the best anti-ledge camper, and Link the worst.
If you're afraid of ledge camping, get a character who can deal with it. It's easily counterable, so there's much less reason to ban it than there is to ban...MK for instance. Besides, ledge camping only works for a few characters. Most characters don't excel at it, so it's not as if everyone can ledge camp for an auto win or something.