I always thought that in Mario's case, the rivalry would boost because as the series is called "Super Mario Bros.", that advertises Mario right there, and the only real characterization Mario has is a rivalry with Bowser. Since the Mario games are all about conflict between Mario and Bowser - a simplistic plot used as nothing more than a vehicle to drive the gameplay - it makes sense for the rivalry to be more representative of the series than either character by themselves.
Link's rivalry with Ganondorf is marketed in the same way. In the original Zelda game, the conflict with Ganon is advertised before the game even starts, and most games in the series are about undoing the damage Ganondorf has done. So the voters perceive this as being a rivalry representative of the Zelda series, fine.
Because Final Fantasy VII is a more plot-driven game, there is a lot more going on, and thus the voters do not perceive a hero/villain conflict to be as representative of the game as they consider the Nintendo rivalries to be representative of their franchises. That's the point I was initially trying to convey.
I mean, I respect the whole point about Final Fantasy VII alone vs., say, the entire Mario series, but that hasn't prevented Sephiroth from thrashing Mario around many times in the past. I can agree that this plays some role, but I think my point plays more.
Argh, I don't even want to talk about this anymore.
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