Created a profile so I could chime in. I am 36 AA engineer and I run into this depressing fact ALL THE TIME. I would guess roughly 35%-60% of all providers blanket refuse AA men. I have always chalked this up to a bad experience as I have known some brotha's to be dubious morally and just a misogynistic. I understand and I am not one to say how someone should handle their business and their bodies. Even so its starts off as being confusing and insulting but after you realize a large chunk of women you find attractive will not see you... or at least until you are 40+ it really become painful to have to experience
I will almost always called providers that had no mention of "no AA" on their profile to either be rejected via the screening. I have even been told to leave multiple locations after arriving. I have honestly been thinking I might just give up entirely since it bothers me so. I wouldn't feel bad but when you see so many ads letting you know your skin color disqualifies you just sux.
Good Luck