Just declare it illegal (national security risks). Treat it like sexual abuse material, scan cloud services for copies, and jail everyone who has them.
They're spending vast amounts of money on the premise that they will be able to monetize it later. A Chinese model with the same capabilities that you can run privately, without obnoxious guardrails, would eviscerate their value proposition. China isn't there yet but it seems it's a matter of months until crossover.
If a ban has to go through Congress then A\OAI will have bled out by the time Congress gets around to doing anything, especially for a law as controversial as jailing people for running Chinese models.
Maybe a similar setup can be done for banned AI weights?