In the case of the author it might be more greed than fear. Producers tell him there's no way the show gets green lit with a white lead, because that's just how show business is now, but they're interested if it's a black lead.

Now if he refuses that, it's just one of a million shows that never came to be and the mob never hears about it to come after them. But he doesn't get any of that sweet Netflix money.