Sure you have a point. If as you state BYU will not be a P5. Okay. Why become G5? Where are the benefits of shackling yourself to a bunch of teams who don’t really care about you or their own position in CFP. So you can compete with lesser teams for a meaningless crown? So you can claim to be cream of the crap?
If you honestly feel BYU isn’t ever going to make P5 status, you haven’t made a case for returning to MWC. Other than you like the opponents better.