I agree with half of what you’re saying—it’s very tough to overcome the allure of P5 schools, their facilities, venues, exposure, and the ability to play against the best. It’s becoming tougher to to compete against this, not easier.
Yet, some schools do it well enough. TCU had incredibly-talented squads while still in the MWC, though not particularly deep. Boise puts more kids in the NFL than many P5’s. IMO, great coaches and/or established programs can still pull it off, at least in spurts.
BYU suffers due to the combo of outside looking in, being passed up by an in-state rival, and a host of self-imposed restrictions. Instead of stability, we’ve had an utter carousel of failed coordinators on both sides of the ball. And we’ll boot you from school over premarital sex, etc.
The school is largely run by people that still remember Lavell’s success but don’t relate very well to the challenges the program faces today or how it is perceived by the current student athlete. It’s not a great model for trying to build a competitive football program, and the growing disparity between us and Utah is no surprise