The players who have a good change of playing in the NFL likely heavily overlaps the players who will be offered endorsements. 99% of college athletes simply aren't good enough for either and will probably be unaffected by this.
I'll bet car dealerships will be the first place in CA that you will start seeing college athletes on the billboards.
And it won't just be the top guys in the state. It will be the top guys on the local team. Even for smaller schools.