So putting those figures into a tax calculator for California. First adjust income by GDP per capita (so marginal tax rates are comparable) giving gross amount

So putting those figures into a tax calculator for California. First adjust income by GDP per capita (so marginal tax rates are comparable) giving gross amount of $183k, at roughly $60k per capita in CA vs $40k in FR. Income taxes /social security is $61k. Employers social security an additional 10K. Then you need health insurance at $8-11k for a single 40yo. Property tax in a median 400k CA home is another 4K a year. So a total perhaps $85k/183k a year in taxes an health insurance. A little less but not all that different, maybe 5% lower overall for someone earning 2.5-3.0x median wage.