From my perspective, the fact that players need to go to college in order to have a realistic chance at joining the NFL is a real problem. When universities act as the de facto minor leagues for football, it creates a whole bunch of perverse incentives. I see it as a sick near-monopoly that exploits athletes while claiming to benefit them.
(Technically, if football players graduate high school and then wait 3 years, they are eligible to be drafted by the NFL. But what are they going to do in the meantime to improve their skills, strength, visibility etc? In reality, to have a chance they have to go along with the whole student-athlete charade.)