I'd argue it won't even stop people in the US from using those models. Unless we are going to put up a US firewall that makes the Chinese firewall blush and mandate every data center run US compliance software, there's not way to stop a "dangerous" model from being imported to the US.

This only stops the likes of OpenRouter from selling access to models. That's it. I'm sure an EU or chinese based alternative will pop up overnight (if they don't already exist).