I see what you're saying, but I still believe it to be an apt comparison when arguing that a moveset can't be varied enough. Still, if we forget the comparison and solely look at Bomberman's gameplay constraints, he's got plenty of moveset potential.
Bomberman's games rely on powerups, much like Mario, Sonic, etc. that alter what he and his bombs can do. His special moves could be bomb-themed to varying degrees, while his basic attacks are just punching and kicking. Not that I'm rooting for Bomberman-- I simply think his more basic games are fun-- but I feel like people who claim he doesn't have moveset potential haven't really played Bomberman games. They just see "bomber" and "man" and think there's nothing else to it.