Uncle Sam always gets paid.
[1] https://www.nolo.com/legal-encyclopedia/how-resident-alien-t....
These things are worth staying current with an attorney every once in a while. I don't imagine it would be very fun to find out the wrong way.
This sounds a bit off. California state income tax tops out at 13.3%, and the vast majority of folks owe less. Even if you include SDI/VPDI, that's only an additional 1.1% in 2022.
The most common tax exemption for foreigners is an exemption from FICA taxes (Social Security + Medicare) [1], which commonly applies to certain folks with F/J/M/Q visas. But generally, they still owe both federal and state income taxes. In fact, as nonresident aliens, their effective federal income tax rate can be a bit higher due to not having the standard deduction and certain other tax benefits.
Another relatively common benefit is the various tax treaties [2]. This may provide some relief from federal income tax, depending on the country and the visa status, but not necessarily a total exemption.
[1] https://www.irs.gov/individuals/international-taxpayers/fore...