The dead weight in each conference serves a very useful purpose. Each conference needs some teams that can easily be beaten in order to give their champ legitimating wins. A conference with total parity would be horrible! If each game was a 50/50 tossup, it would be very rare to have a champion with a "good" record. As a result, the conference's bowl invites, recruiting, and prestige would suffer. So teams like Kentucky and Vanderbilt (SEC) or Colorado and Oregon State (PAC12) or Iowa State and Kansas (Big XII) are willingly kept because they provide easy, high-value wins for in-conference foes.

Additionally, many of the schools that struggle in football have good programs in other areas. Kansas, Iowa State, and Kentucky might be bad at football most years, but they also have pretty good MBB teams. There's value in that.

I have no idea what BYU's next broadcasting deal will look like. But they'd better start winning, or it's going to be hard to draw enough eyeballs to get appealing offers.