On its face, UK is a top 4 job in CBB, yet several elite coaches turned them down to stay in less prestigious roles. Many of them (notably Hurley) turned down even more money than Pope is going to get. And let's not forget the other red flag, that Calipari chose this as the best time to step away, not to go into retirement but to take the reins of a much smaller program.
The issue I foresee is that Pope did not have a resume worthy of Kentucky. He shouldn't have been in the running for a blueblood job, at least not yet. If he had the right kind of resume, he could have sat back and waited for a better opportunity to jump into a bigtime job. At the very least, he would have been afforded a lot more slack than he's going to get, being so underqualified. I could see Pope eventually regretting taking this opportunity, not because he left BYU, but because he skipped several steps that a coach is usually expected to make on their way to a blueblood position.