Another sibling thread already called this out, but mentioning here: it's not "USA only", it's "US citizens only" (and I'm not entirely sure how dual-citizenship interacts with this, but I assume you can't sell to them, either, since they are by definition also foreign nationals). A private company only being able to do business with folks they can verify are solely US citizens (who themselves are also willing to submit verification of said citizenship to a private company), has a relatively small pool of potential users.

And so if this policy holds, Anthropic has functionally had Fable killed by government intervention, and in a logically consistent world, this would imply all other US-based AI labs may also never exceed existing (read: Opus) capabilities.

What interesting times we live in, indeed.