Here's a hypothetical (and not advocating for it, more this is a what-if exercise and trying to anticipate where a "salary cap" might get put into place)...
What if a majority of college football programs push for national legislation? Specifically, a law that sets a maximum collective NIL wage for a college athlete at $100K per year, indexed to inflation? Or something more generic, such as "no enrolled college student can earn more than (x) times more than the average earnings of all students at the same college"?
Maximum wage laws in general have been talked about in the past. Would a maximum wage law targeted at a subset of the general population (i.e. college students) pass legal muster?