Anecdotally, I feel like it isn't, though I don't live in the Bay Area. San Francisco has the highest GLBT population (by percentage) in the nation. Even if we even it out and use 10%, a number that GLBT organizations sometimes use when referring to the general population, that would imply that most startups with a 10-person engineering team would have a gay engineer.
In my experience, that's certainly not been the case, at least in NYC (though it seems to be true about SF as well). It's even more bizarre because Silicon Alley overlaps with most of the gayborhoods in NYC. At a startup I used to work at, our local dive bar happened to be a gay bar, even though only one member of the team was openly gay[0]!
[0] Backstory: the old dive bar got bought and turned into a gay bar, so people just kept going to the same place anyway.
In my experience, that's certainly not been the case, at least in NYC (though it seems to be true about SF as well). It's even more bizarre because Silicon Alley overlaps with most of the gayborhoods in NYC. At a startup I used to work at, our local dive bar happened to be a gay bar, even though only one member of the team was openly gay[0]!
[0] Backstory: the old dive bar got bought and turned into a gay bar, so people just kept going to the same place anyway.