The NFL doesn’t have a minor league. They depend on colleges to produce players. It’s up to the colleges to have the same academic standards for atheletes as the rest of their students. In addition to that, they’re getting sports scholarships. I’m amazed they aren’t revoked for criminal behavior.
When I was at FSU if you needed an easy quarter you followed the football players through registration. They had one course and I kid you not it was called “Trucks and Trains”. :-)