1. Mark Pope didn't get fired, because BYU had a great season. That means the complainers in your post were wrong. Just as they would be now if BYU has a great season and Kalani leaves for a blue blood job.
2. Name me a top NFL assistant who would be our Kevin Young. Kellen Moore? That seems like even more of a pipe dream. But I'd be very excited about Kellen Moore.
3. Who was the backup option if KY said no? Chris Burgess, probably. I like Chris Burgess. He obviously doesn't bring the same buzz as KY.
4. Who is our backup if Kalani gets fired and KM says no? Jay Hill, probably. I like Jay Hill. At least among the population on CB, he probably brings more buzz than Chris Burgess would've for basketball.
5. Does Kevin Young come here if the season had gone so poorly that Mark Pope does get fired? That's an interesting thought experiment. I think he probably does, but who knows.
6. In that vein, would KM leave the NFL for a rebuild at BYU? Because if KS gets fired, at that point, we have to admit that BYU has to undergo a total rebuild.
7. The job of the BYU basketball coach is very different from the job of the BYU football coach. Totally different animal.

It's not that I totally disagree with your premise, just that it's a crazy oversimplification of two very different situations.