I just told my wife that's amazing. If you watch any TV, you would think the US population is 25% homosexual, 50% Black, 25% Hispanic and about 25% White. . . Don't watch much TV here. . .
Well, in NYC, LA, and SF, (where the lib writers live) the gay percentage is probably much higher than the national average.
On TV, though, they do have a tendency to have any roles that portray authority figures (judges, chief doctors, etc), particularly bit parts, being cast by blacks, women, or preferably black women.