food - most of what i saw was not good food. hipsterish overpriced food made by chefs trying to show off by putting a twist on dishes -not to be good, just to be different or weird. tiny portions, not tasting above average, on a huge plate. all presentation, not actual taste.
culture: there is no culture. culture was when i lived in versailles. sf is all snooty people with no content, trying to show off. culture is down to earth, with class.
bars -there are very few attractive girls at bars, or at offices, or even on the street, compared to just about anywhere in the world. and if that's not why you go to bars, i have to ask -you'd enjoy going to bars with mostly men? because that's cool too -once in a rare while.
density is poor in sf. in good cities, you can walk where you want in a few minutes. sf is uber heaven. i've lived in cities with amicable density - without a car, and maybe grabbing a cab once a month. sf ain't it.
the weather's not bad, a little windy. and the ocean is close by. housing prices are being kept artificially high by sf itself -not letting people build housing.
so i can't see anything about sf that'd make people want to live there other than higher salaries. and the first chance they have to earn that salary elsewhere or remote, they jump on it.
so i think that's what's happening now. nothing to do with covid directly -just people who would never live there in the 1st place if it wasn't for the job, leaving as soon as the job lets them.
i think all this analysis of what people are doing and why weirdly avoids the very simple explanation -everyone's just doing what work lets them do. it's entirely dictated by employers.