38% decrease in people moving to California 12% increase in residents moving out of state last year.
In San Francisco Bay Area, it's even more stark. There was a 45% decrease in entrances from other states to the Bay Area and a 21% increase in residents leaving for other states.
People halting moves into a dense population center because the city shut down for covid is not the same thing as people "fleeing in droves for taxes". There are absolutely some people doing this, but you are making up connections and this is a lazy talking point.