Brett Kavenaugh and friends haven’t ruled on NIL limits have they?
You should read Kavanaugh's concurrence in the case. What he did is called dicta. It's when a judge foreshadows what a future ruling would look like if certain elements of the case were brought to the Court again. Even though the Court reaches no decision on the merits, it's a guidepost. He said, in his concurrence, that restraints of trade by the NCAA raise serious antitrust questions. He said that not calling students employees raised antitrust questions.
Judges usually don't go out of their way to do this unless they individually want to get it on the record or if they know they have the votes should the issue come to pass. Given that Alston was 9-0 and Kavanaugh wrote a scathing indictment of the NCAA's model in his concurrence, one can consider the possibility that the dicta was both because he wanted it on record
and he has the votes behind his reasoning.
Specifically to a cap on benefits for student-athletes, he says:
If it turns out that some or all of the NCAA’s remaining
compensation rules violate the antitrust laws, some diffi-
cult policy and practical questions would undoubtedly en-
sue. Among them: How would paying greater compensation
to student athletes affect non-revenue-raising sports?
Could student athletes in some sports but not others receive
compensation? How would any compensation regime com-
ply with Title IX? If paying student athletes requires some-
thing like a salary cap in some sports in order to preserve
competitive balance, how would that cap be administered?
And given that there are now about 180,000 Division I stu-
dent athletes, what is a financially sustainable way of fairly
compensating some or all of those student athletes?
Of course, those difficult questions could be resolved in
ways other than litigation. Legislation would be one option.
Or colleges and student athletes could potentially engage in
collective bargaining (or seek some other negotiated agree-
ment) to provide student athletes a fairer share of the rev-
enues that they generate for their colleges, akin to how pro-
fessional football and basketball players have negotiated
for a share of league revenues. Cf. Brown v. Pro Football,
Inc., 518 U. S. 231, 235–237 (1996); Wood v. National Bas-
ketball Assn., 809 F. 2d 954, 958–963 (CA2 1987) (R. Win-
ter, J.). Regardless of how those issues ultimately would be
resolved, however, the NCAA’s current compensation re-
gime raises serious questions under the antitrust laws.
To be sure, the NCAA and its member colleges maintain
important traditions that have become part of the fabric of
America—game days in Tuscaloosa and South Bend; the
packed gyms in Storrs and Durham; the women’s and men’s
lacrosse championships on Memorial Day weekend; track
and field meets in Eugene; the spring softball and baseball
World Series in Oklahoma City and Omaha; the list goes
on. But those traditions alone cannot justify the NCAA’s
decision to build a massive money-raising enterprise on the
backs of student athletes who are not fairly compensated.
Nowhere else in America can businesses get away with
agreeing not to pay their workers a fair market rate on the
theory that their product is defined by not paying their
workers a fair market rate. And under ordinary principles
of antitrust law, it is not evident why college sports should
be any different. The NCAA is not above the law.