Can be tied largely to two things:
The meteoric rise of Utah. The vast improvement of Utah State. There are a finite number of D1 players in this state, or who will come to Utah to play. Utah has the P5 thing, and whether you want to admit it or not, Whittingham is a great football coach. USU has easier academics, no other restrictions and is on the rise. These things are cyclical, but both have hurt BYU. Both have several kids on their rosters who would make BYU better. That wasn’t always the case, especially with USU.