With all due respect to taxes and fiscal issues (and they are paramount in this example) there is another side to this.
With California (and New York) suffering net population decreases magical things start happening. Yes, the tax base falls. But it also has impact on the lives of the "stayers" as housing values fall and per capita costs must increase. But then there is the far more subversive part... there could be a loss of congressional seats and a hit in the electoral college.
I'm sensitive to this because MN is undergoing this phenomenon. Who knew that bad weather and high taxes would make people leave?