I can't speak to San Francisco, but in Seattle at least, I never saw any flyers or graffiti telling LGBT people they were unwelcome and should leave town, nor did I ever encounter political discourse that LGBT people were somehow ruining the city, or scapegoating the LGBT community for local issues. So in my personal experience as an LGBT software engineer, I wouldn't be surprised if San Francisco was the same way.
Me too, and in 2014 someone tried to burn down Neighbors with hundreds of people inside, and before the pandemic gay couples reported being harassed and assaulted for walking down the street in Capitol Hill, and I heard more than one guy entering different bars (again, in Capitol Hill) cautiously check that this bar didn't have GAY PEOPLE, right? So I think the idea that tech people are less welcome than gay people is a horrendously uninformed one.