Here's what I think: I think that if a group of gays say they chose to be gay and another group of gays say that they didn't chose, then it's inconclusive. We could speculate that one side is confused and the other side is right. But then again, that doesn't prove anything as there is no proof to who is right for certain and who's not.
The proof isn't the person's opinion because there's multiple opinions.
I guess there is no way of telling, only our own personal opinion. I say that I didn't chose. Your friend says he does. That kinda cancels it out and kinda doesn't - that simply means there's no way of knowing. If you think of it that way, it's a stalemate...