While I largely agree, I’d raise some limits about the basic principle that people will move their domicile to avoid taxes. People do move to avoid taxes all the time, but it’s nowhere near as simple as saying that people will quickly move to wherever taxes are the lowest; people will tolerate some level of higher tax if they feel that it’s worth it for whatever reason.
At the low income end, that’s been CA for decades. CA is a higher tax state than other places, but they could get away with it because people wanted to live in CA, and were willing to pay for it. It helps that the really desirable areas of CA are a long way away from other states, making leaving the state kind of a pain in the butt. It’ll be interesting to see how Covid changes that around.
Even at the higher level, we don’t see a ton of millionaires and billionaires renouncing their citizenship and moving to wherever the taxes are the lowest. Some do, but a lot stay in the US because living in the US is a really nice place to be if you’re rich. They might move to the lower tax states, but that’s as far as they’re willing to go.
The issue for SF specifically is a bit like the issue for NYC; it’s relatively small and really close to a bunch of places within commuting distance that have lower tax rates. Compared to leaving even CA, leaving SF specifically is really easy.
And FWIW, I think that the tax thing is a bit overblown; I think housing costs are the real problem. I’m leaving CA (Los Angeles) next month for another state, and while I’ll save a bit on taxes, it’s nothing compared to what I’ll save on housing costs. Four months of owning a home will save me enough over my 2bd LA apartment to obliterate any difference in income taxes for the year.