Hate to say this but there is nothing about the online space that makes people homophobic fascist, it's just in online games anyone can join from the most fucked up backgrounds. In far too many online games there is inadequate moderation, on PC there is almost always the admin on every server ready with the ban-hammer. But on consoles, anyone can plug in a mic and spew insults for entirely sadistic reasons they only do it because they know they will cause harm, usually they go without any punishment. Try that in real life, you'll get banned from any private function (pub/cinema/arcde/etc) and on the streets you'll get excluded from the rest of the world and be put in jail.
For the time being the best solution is simply - and I have said this a dozen times before - just "mute player". I don't know how it is for gays but I personally don't like these socially retarded pre-teens scream "GGGGAAAAAYYYY" at me just because I am killing them so often. No one is safe from these immature dickweeds and they will just say what every they think will cause most offense... because their playing skills suck so much they have to compensate.
As to actually getting these social retards to stop with their prejudice, good luck. Though one thing a strict etiquette can do is not popularise gay-bashing amongst other users and one way to achieve this is to vote-mute an abusive user, so no one even has to have the inconvenience of individually muting him, the abuser then knows that their conduct is not accepted. Peer pressure is a powerful force, getting voted off is an effective social punishment.
As to why gay-bashing is used as such a common insult even against obviously straight people, well I blame the gay community for this one. The gay community think they will get their way by differentiating themselves and being "visible" so they can't be "ignored" when all it does is alienate people to homosexuality. I mean gay pride parades do nothing but enforce stereotypes and how is anyone going to come out of the closet when his sexuality is represented by farcical pantomime.
Gays need to be re-branded. Confident, responsible and empowered, not flamboyant and effeminate. Imagine all the horrible racist stereotypes of African Americans and put on a float as part of a "black pride parade". Counter-productive, no? Where are the openly gay sportmen? Openly gay action protagonists like Omar of the unappreciated 'The Wire'?
Take the UK, my home town. There is no gay issue here. Why? Because openly gay people have made them self popular with the majority of the Heterosexual population by being great entertainers, comedians and TV presenters. Has there EVER been an openly gay TV presenter for say a TV game show for the mass American audience? Yet Americans like Perez Hilton think they can just whine, ***** and moan till they get their way. Doesn't work like that. If they keep up with this "them and us" attitude then California's Proposition 8 will not be the last anti-gay legislation. They are only 4-7% of the population, they NEED to be popular as you can't just vote HARDER, American gays MUST endear themselves to average straight people, not as a "poor me" pity-case but to defuse the paranoia over what many people see as a perverted lifestyle choice.
A city has nothing to be proud of about having a "gay district" as in my mind it is the moral equivalence of Jewish or Black Ghetto. America needs integration, not segregation.
I usually don't get uppity with America (kick ass country by the way) but on the gay issue you are completely wrong. Even the liberals among you seem to treat gays as a different species. Maybe it is because you have so much of that uncompromising "macho pride" which never really worked for us and in the UK there is no perception that gays are a threat to average straight people's way of life so there is no moral reason to tolerate abuse that is clearly targeted at them.