If I only played games with subject matter that interested me, I wouldn't play games at all. Describe me the premises of my top ten favourite games, and I just wouldn't give a shit.
Almost every single game I play, no matter how much I enjoy it, forces me to play a role that is diametrically oppposed to my own beliefs. The situations that come up in these games bear no relevance to my life at all, and I don't expect to ever play a game where they do.
There's simply no way I'm alone in this. Take the most clear-cut example of populist macho heterosexual idiocy, Gears of War - no matter how much somebody enjoys the experience of playing that game, I refuse to believe more than a small percentage would genuinely identify with what's going on. It's pure, silly, escapism.
And that's why it makes perfect sense that gay people would feel alienated as they play games. It's because they're people playing games. It's a form of entertainment that is inherently based around role-playing. You're never yourself when you play.
I share the wish for more LGBT themes in games, but only to diversify the incredibly narrow field of subject matter, to demonstrate the maturity of the industry*, and because I believe that such themes are in danger of becoming taboo, which is a terrible thing.
*as always, displays of 'maturity' must be approached carefully, because they can - and usually do - backfire hilariously