The goal of this initiative from the nurses union was to replace the federal Medicaid payments eliminated by the BBB. Forbes has been misreporting the billionaires in CA, but once adjusted for reality the initiative will bring in about $15B/year, helping bridge the gap to the lost $20B. As Albaby pointed out, court challenges may eliminate any gains.

With the current red hot stock market CA is minting billionaires fairly rapidly. The high end housing market in CA is robust with mostly cash buyers.

We heard similar arguments when CA implemented the "millionaires" income tax, but the impact was nearly unmeasurable.

Leaving CA will have a MUCH, MUCH larger impact on lifestyle than the cost of this tax. Some of those leaving are making a political statement, and some of them would have left anyway for other reasons. I would suspect this is just one of many factors. For instance, I know several families my age that are leaving so they can be closer to family. Living in CA is VERY expensive so many relocate to lower cost areas.

It is easy to underestimate the size of the CA economy, which currently has a GDP of $4.25T, with a population of around 39.5M.

IF this policy is implemented it will likely follow the path of the millionaires tax and be much ado about nothing.
Alan