The biggest mistake NCAA makes in all of this is never threatening to do stupid ****.
They should be floating these kinds of ideas out there. "We are looking at removing all eligibility requirements." "We want to remove all grade limitations." "We will be removing all roster size limits." "All professional players will be allowed to rejoin college teams." "The portal will noonger be timed-capped, it will be open and usable at all times." "There are no limitations on in-season transfers of players."
Put this sort of stuff out there. Put out threats of the most outlandish, completely system-breaking changes possible. Then, when asked about it, feign being powerless by threat of legal action if they did continue restricting these things.