I think that's more because blacks are thrown right into a breeding program based on color alone, so they rarely see the show ring.
My bay mare Nadira is sired by a very nice Black Arabian. He is a race and endurance winner. Unfortunately, a pasture accident kept him from becomming a "big" name.
And here is my filly, pictured below at a year old.
She is a *Simeon Shai and Nykoli+ grand-daughter. Not sure if she'll hit the show ring or not, her partnered owner would like to use her for a pleasure horse (trails).
2 years old
Have to get decent photos of her in the spring. She's a BIG filly pushing 15.1 barefoot and I'm not measuring with the "Arabian stick" as I do not care about height being only 5'5. She has a lovely, classic head as well that her super thick and long forelock likes to hid. :sigh: