I mean, it would be no surprise to me that Duke, Kansas or Kentucky have more valuable, more profitable bball brands than other schools. They wouldn't have this without consistent winning. So, clearly, a few NCAA championships can build something valuable over time as well.
Probably the fact that I'm an alumnus of one school really puts me outside what might be considered "persuadable fans". Kansas basketball is not a major brand because they're going to convince middle-aged alumni of other schools to root for them. The extra brand value probably comes because kids growing up with no particular school connection might root for them or because their relevance makes them a draw for non-fan TV viewers.