California can just keep doing its thing and the rest of the country benefits from their regulations. Prop 65 is to thank for all the Harbor Freight stores no longer reeking of outgassing plastics.
If there's one thing California needs to learn from these past 6 months, it's that you can simply ignore what the courts say. When you're rich and powerful, you can literally just say "I do not consent" when legal consequences are presented to you.