watching the game again is that BYU won the game with a fairly average game for them.
There wasn’t anyone player or a collective play-out-of-their-minds effort. There wasn’t any crazy outlier stats on D or O. It was an average solid effort by a good BYU team. You could probably make a case for above average D.
My point is that BYU is a solid team that played their usual solid game and beat a very very good team.