I could see a world where the P3 breaks away and implements salary cap types of regulation, but like you said there's just too many good players, schools, and markets to break away with only ~40 teams (especially if Northwestern, Vanderbilt, etc are still making the cut).
But that doesn't mean that there won't be a distinct difference in resources, and we need to do our absolute best to keep those resources as even as possible. If FSU and Clemson are actually a possibility, it would be insane not to do everything in our power to get them into the B12.