I think if teams paid directly a lot of the outside money would dry up. Why pay a player directly when you can pay the athletic association and let them deal with all the paperwork and all? Trying to get around a salary cap is a potential reason, depending on just how deep some of those pockets go, but I don’t know where the numbers would land. AFAICT, we aren’t seeing any programs splashing out 8 figure payrolls yet.
“True” NIL endorsements would be hard to prohibit but, like in the pros, probably not the biggest thing separating team A from team B in a player’s mind.
If the teams and the players are directly contracting for employment you can do a collectively bargained cap, including things like max individual salary restrictions intended to promote competitive balance, just like in pro sports. You don’t need an antitrust exemption for salary caps, the NBA and NHL don’t have those. Just a league and a union. Versus NCAA attempts to dictate to players.
GT would probably need to raise more money to compete but depending on where the cap lands that might actually be more realistic. It would be interesting to see which schools lobbied for higher caps and which ones wanted lower ones - are there enough programs out there that want to/can afford to spend 40million (random number pulled out of my hat) on salary a year that a league with that high a cap, without subsidies from the “haves” a la pro sports? I don’t actually think a 30-team all-Southern and Midwestern super league would be that financially viable for long.