Plus there's the fact that NBA is pretty much the only thing 2K has going for them right now. I don't see them jumping into the fray.
As a whole 2K has a lot more going for them then one might think. They have Bioshock and Borderlands series and GTA V. But sports wise, yeah their bright spot has always been NBA. MLB series sucks and the previous attempt at college football was bad. But I'd be interested to see how a new spin on football would be with next gen graphics and possibly a NBA 2K-type feel.