Not that there were zero, just that they were rare due to entry barriers. If you have evidence to the contrary I would love to see it rather than listen to your pathetic attempt at a clever put down.
I don't know, but I don't find it hard to furnish ideas. Colleges used to try to ensure they didn't produce more professionally qualified graduates than there were entry-level positions for. Perhaps colleges only graduated fewer black students than there were openings in black-owned enterprises?