A mix of stereotypes and truth. I think like most things in life, theres a bit of truth in every "lie".
But to be honest, I dont think I've seen a lot of "no black men" places outside of Chinese only spots. I think every spot has their own quirks you just shrug and move on. Theres even chinese spots i've seen where chinese women wont serve their own people chinese men lol. And korean girls who dont serve korean men for some reason as well ?
And the vocal minority ruining it for the rest of the guys who are not dickheads.
One example I'd give from going in NJ. I've overheard quite a few times from inside the rooms the guys outside in the lobby complaining about the tip, having some sort of attitude with the MMS and providers asking about how much the service is, what kind of service theyll give and saying shit like "shiiit you gonna take care of me right for how much im giving you" and overall just giving the girls/people working a hard time.
From conversations with the chinese girls, even the J girls in manhattan. Again not me stereotyping but what the girls say. Is how they have bad experience with darker skin people like indians and black men. Where the guys are violent , super aggressive for no reason, rude etc. Biting , leaving hickeys, just trying to ram these girls rather than treating them like human beings.
But yea as much as people go with the ego stroking convo of how its because they are big. I think its mostly a vocal minority just being dickheads that make the providers/locations straight up saying they dont serve them. That and prior experiences they have with robberies lol are a deterrent as well.
Sorry you feel that its a bad experience ! Not all places have these restrictions. And luckily most places dont like almost 95% or more lol.