I actually just went and looked at this; over the last 3 years, BYU is behind not only Utah, but Memphis, Cincy, UCF.
https://www.cougarboard.com/board/message.html?id=25292603
More to the point, as a relative newcomer, out West, and with a crappy TV deal, Utah is actually pretty terrible at drawing viewers (compared to P5).
This isn't a transfer who is leaving because he can't get time. This is a stud NFL prospect leaving because the program is in disarray. I don't think he's going to Utah either. Being from California, I'd bet UCLA or USC or some other place where he can get exposure that dwarfs either BYU or Utah