Even if they're not playing in the NFL for 2,3 or 4 years, pu them into a developmental league where they can earn $30K a year for a shot to make the league.
Then college is reserved for people who want to go to college, not for people who have to go because that's the collusion that's been designed. It's been designed to protect the value of college football, which exploits poor athletes who otherwise have no way to make a living in sports.
The system is likewise awful for college athletics. Kids who have no reverence for school (why should they) break the rules, break the law and are coddled because they make millions for the university with no pay. Then we all have to pretend like we care about academics in student athletes, coaches impose 1-game suspensions during the 1-AA game week and everyone happily looks away.
Major League Baseball has solved this - you may be drafted out of high school, but once you start college you have to be out three years. It preserves the notion of amateur athletics - of trading your athletic skill for a shot at a degree - without forcing people to take that route.