Most FBS conferences have a rule you can't play a FCS school at their home in football. That would not apply to Army as they are independent. It is very tough to for a FBS G5 school to Get a home game with a P5 school

FBS college Football is the only sport in the world that you cannot tell all
Of the members classified as FBS (128 schools)win all your games and you will be
The Champion.

Heck if each of the 10 FBS conference champs ended up
Undefeated only 4 would go to the playoff and the remaining
6 undefeated schools would not. It is by far the dumbest system ever

Let's see NFL. 28 teams. 12 go to the playoffs and they are considering going to 14

College football FCS ,division 2 and 3 all have 20+ teams in their playoffs

FBS. 4 teams. Total BS. The power conferences don't want a G5 team like a Boise State or Houston or WKU ever to get in the playoffs because should they win all bets are off. You don't think that's a recruiting advantage to say only 5 of the 10 conferences have a chance to ever play for a national championship.