I have no issue with Nick Saban making $10 million. He definitely earned it. I have an issue with saying that Nick Saban helps Alabama win, winning makes a ton of money for the school, therefore he should be paid a lot -- but then saying that the players help Alabama win, winning makes a ton of money for the school, but they shouldn't be paid because they are 18-22 years old.
Going by your analogy to the big corporation, no corporation would ever say, "We're making a ton of money, we're giving our CEO $10 million+, and the great news is we don't have to pay our lower level workers money because we agree with all of our competitors to never do that under threat of penalty." That would be extremely illegal which, in fact, is the exact reason we have NIL now.