> I'm not sure, but it's been a little surprising to me as well.
When you have the income to:
1. Rent a comfortable apartment pretty much anywhere in the Bay Area, without fear of rising rent displacing you. (Keep rent within a third of your income)
2. Pay for a private solution (Rideshare, Private commuter buses, tech company shuttle) to the broken transportation infrastructure, dirty streets, and the homeless problem of the Bay.
3. Have a fiscal safety net in case something happens to your income.
4. Have the insurance needed to withstand the occasional curve-balls of life.
then you've mostly averted the endemic problems of the Bay Area. SF's gov't is incompetent, and private solutions have alleviated most of its systemic issues for its moneyed classes. Of course people in tech won't be as motivated to vote, they're insulated from all of the problems.
There's a growing sentiment (growing being an understatement, Google/Apple buses have been smashed/blocked for years now) that tech's private market solutions are priced to only help their own out. Until this perception changes, they're going to want to vote with their rage.