Games in general are just starting to get real physics engines so you are right about this. However, the real hurdle to fully realistic gameplay is AI. Your theory of making games totally realistic with AI that just gets smarter is indeed what these guys should strive for.
However, AI is insanely complex in team sports games and I don't think we've reached a point where totally realistic AI can even be programmed, much less handled by today's systems. While the PS3 and 360 have considerably more power than their predecesors and that helps with graphics, their added power is a drop in a bucket when compared to what would be needed for truely realistic and sophisticated AI.