It's fun to think about but also completely unworkable for college football. Most athletic departments outside the top 20 are breakeven at best and many actually require subsidy from the university to be solvent. Texas is far outside the norm here with the revenue we throw out of the AD. Since football is the #1 revenue generator, if a more marginal school was relegated, their revenues would tank even further. Imagine being an Iowa State or an Arizona St., or Purdue or Ole Miss and you string together a few bad years and relegate down one or two levels. All of the sudden your conference schedule is what we know today as MAC, Sunbelt, and AAC teams at best. Your TV revenues tank, your gate tanks, and now your whole AD is insolvent. You have to cut a ton of headcount out of the AD and, probably, cut a bunch of other sports too. Especially women's sports, and now you have a Title IX issue. It's a death spiral. In european soccer a rich owner plugs that gap and invests to move up. In CFB, the "owens" are the donors, much more fickle.
Also worth pointing out: in this system how far down would Texas have relegated from 2010-now? 2 levels? 3? Interesting to think about