Explain, please.
Are you saying vendors from out of state must pay taxes in Calif if they sell to Calif?
If so—I would tell such vendors to stop those sales. OR-—jack up the prices accordingly ++++++.
That’s the way I interpret it. Here’s the link again so you can read the rule and make your own conclusion. It’s just insanity.
https://www.ftb.ca.gov/businesses/New_Rules_for_Doing_Business_in_California.shtml