Great way to help would be to ignore the PC nonsense and, if you love your gay black friends, ask them to get tested! You can have it for a while and not know, thus spreading it and putting your health at risk. By ignoring the elephant in the room and trying to be PC about it you're literally the worst friend they could have. And if you're a white gay you might as well take your own ass to get tested too because the rates are nearly just as high

(unless you aren't sexually active or you know they aren't then don't bother obvs).
But yeah this is due to a huge lack of education, "down low" culture, homophobia in the black community and racism from every other direction.