There's no effective way of enforcing export controls on local software like PGP etc. Whatever they say someone will leak it.

It is possible to shutdown access to hosted services, as happened with Fable, but it can't really be done selectively. The US government wanted to allow it for US nationals only but Anthropic couldn't do that and so shut it down for everyone. Even if they did tie Claude accounts to nationality some people would set up "proxy servers" to allow access (either for montetary gain or because they don't agree with the restrictions)