I can't say I know much about Pittsburgh's culture, but I wonder how it would have held up over decades of insane money being pumped in and wild rent increases? SF has changed a lot over time, but it has a boom town history of being invaded by hustlers looking for money, so I guess that's something. Gay pride has persisted in SF as well, strong pockets of Asian culture, a saucy underground, etc... Tech has definitely left a mark, maybe not physical libraries and concert halls, but Long Now and the Internet Archive are doing good work to preserve culture.