Just look at Bill Belichick. He's horrible at PR and is often a jerk with the media. But he can get away with it because he's won three Super Bowls and he has his team in playoff/Super Bowl contention almost every year. He's one of the greatest coaches in NFL history IMO.
Same thing with Nick Saban. I wouldn't say he has good PR skills and he is also a prickly pear with the media. But again, he gets away with it because of his on-field success and national championships that he's won.
Bronco's resume isn't even close to those two guys and therefore doesn't justify him having bad PR skills. I think especially at a place like BYU, it's important to be good at PR and know how to deal with the media. But Bronco doesn't really seem to care that much about it.