Quite simply it depends on whether you include reaction speed and toning of reflexes in "skill". If reflexes are included the answer is clearly Tekken. That game is less move knowledge and more knowing opponents moves and being a fast reactor (for counters, quick strikes ect). It is quite possible in Tekken to go game upon game vs decent opponents without taking a single hit using someone fast like Nina through quick reaction speed.
In terms of difficulty when it comes to understanding the system and moves then Virtua Fighter is harder (though less demanding in terms of lit fast reflexes). Mastering the high end combos in Virtua Fighter is way harder then the 10 hits in Tekken (which seldomly work anyway). Despite that I find Tekken to be loads more fun; tekken 3 is STILL a blast.
Smash bros is, more or less, a joke game when it comes to fighting just like Mario Kart is when it comes to racing. Yes there is strategy and reflex involved, but it is just not in the same league as a game like Virtua Fighter. Smash bros is to other real fighting games what Mario Kart is to a game like Gran Turismo. I mean Smash bros is fun and all, and I know some people REALLY think its hardcore (I played with some friends who actually had a league going for it) but its just not. Someone with limited skill and great reflexes will win in Smash Bros every time; that game is 99.9% reflexes once you learn the basic moves with your character since the move list is so limited. Vs anyone good its a boring hour of roll blocking, there is not the complex difficulty of countering opponents you find in Virtua Fighter or Tekken.
Thanks for clearing that up. Next time, maybe try reading a few posts up and attempting to deal with the posts of the people who do think it's a hardcore game (which it is, as I've proven many times).
And of course Mario Kart is a real racing game! Just because it isn't 'realistic' means nothing--in fact, some people (not necessarily me) would call GT less of a 'game' since it's closer to real life.
I love how people constantly end up dismissing SSBB as a game with "less" skill because they are honestly incapable of recognizing the types of higher level skill that it actually implements. I'll admit that I may be dismissing some of the types of skill necessary to other fighting games, but not nearly as much as what people dismiss from Brawl. they may be totally and absolutely unaware they're doing it too. They're just simply so stuck in using their own styles which doesn't even scratch the surface of the skills Brawl implements.
Impulsivity has a point, Brawls biggest skill focus is in the reflexes, but that's not the only skill it involves. There's also Terrain use(both the distance between your enemy and yourself, as well as being able to avoid and guide your enemy into obstacles on the stage), character vs character strength and weaknesses, vertical fighting (moving up and down in order to perform and evade attacks), Time vs Stock tactics(tactics needed to get the most kills are incredibly different from only needing to be the last person standing), Item aquisition/use/evasion tactics(99% of all items can be evaded/neutralized with a high enough level of skill, including hammers, assist trophies, pokeballs and smashballs), Tenacity (avoiding the finishing blow and getting back on stage, even if at extremely high damage), edge guarding (making it as hard as possible for your opponent to get back on stage), juggling (essentially Brawl's version of combos, but requires plotting trajectories more than button memorization), and then of course basic prediction tactics of learning your opponent's individual style(one person using marth can have an entirely different style from another person using marth)
There are a variety of skills that are present in Brawl that are never even remotely touched on by other games, so people who are steeped in those games will likely never be able to recognize the signifigance of those different types of skills.