They basically telling SMU, "you ain't got nooooo shot unless you win the ACC." Boise State, they don't want them shocking any big brands again.
They're not going to let both the B1G and $EC fall too far. They'll just keep swapping teams throughout conference play.
Gotta remember it's not actually a playoff. It's an invitational tournament. Only the four P4 champs have a clear/unbiased path to the tournament. G5...you gotta be ranked higher than the other G5 champs, so that's subjective. The other spots are there to give B1G/$EC more revenue and opportunities to win it all.
System is designed to keep the lesser schools out. You could have the 2024 NFL All-Pro team, but if you're wearing the wrong laundry, you ain't getting in.