1. This is a decent rule of thumb, but is not applicable to all.
2. I love everyone that roots for BYU and I think more people should root for BYU.
3. College sports is really getting more and more disconnected from the lives of students. I love the BYU teams, but the only thing we have in common now is basically laundry. This is enough for a lot of sports fandom (it's not like I have a lot of overlapping history with the Dallas Mavericks or anyone else), but the connection between normal students and athletes is less than it ever was. We still have in common our faith (in many cases), shared experiences (attending games makes an impression) and some shared geography (I have eaten at the Legends Grille), but these guys are in a different universe than I was more than ever before.

Anyway, in the same way that I think it's no big deal whether you prefer BYU Creamery milk vs some other brand, I don't know that the norm of rooting for your own college's sports entertainment business over all others is as crucial as it once was, either.