The easiest one to point to is property prices. Wealthy people buy land, and drive up the price of land and rent for everyone else. If a lot of people suddenly make a lot of money in San Francisco, in general, for me and most of the people I know, there's no "rising tide" that lifts our boats. Our income remains the same, but our rent goes up, and maybe our lives don't make sense anymore, and we have to move.
But if there's a wealth tax, and it encourages rich people to leave the state? Awesome. Go drive up rents in Texas or Montana or somewhere else. Or pay the tax, and then the state can use that money to build affordable housing.
Before you say anything: I lived through the 90s, and you can't trick me with "WOW YOU THINK THE GOVERNMENT CAN DO THINGS? WHAT ABOUT THE DMV???" Go somewhere else.