I am not in the industry so I really can't be certain one way or the other.

What I think is sence most straight porn is purchased by straight men and sence most straight men don't want to see men fucking each other that is why the only homosexual scenes are between women. I think that if the industry was as homophobic as you claim that there wouldn't be any DP's or gangbangs. If they really were homophobic they wouldn't want to be that close to another naked man.

Just my opinion, for what it's worth, which probally isn't much.