The big problem Anthropic faces isn't implementing a KYC workflow, but the fact that many if not most of their own employees are no longer allowed to work on Fable/Mythos.
Also their API customers and downstream customers (e.g. Cursor users) would also need similar infra, and probably a decent amount of users would just choose another model that doesn't require ID & an immigration status check.
And API is much more profitable (relatively) than subscribers for them.
I think it will atleast take one month to set up correct flow for user authentication for both their subscribers and for API's (Cursor etc).
Others are thinking such a export control ban is good for them as it shows entire world Anthropic models are best, I disagree. It will wreck the company, IPO considerations etc, when the models may be best but their are no users to use them.
If such an export control ban stays in place for this particular model or future models of Anthropic, revenue will be affected. My guesss is around 50% of subscribers are non-US citizens, meaning direct 50% revenue loss.
Altman/Musk used to also do moral superiority, "Dangers of AI", lobbying to ban "non-safe" models etc. But they largely stopped doing it after 2025. While Anthropic/Dario increased the intensity of moral authority, and got hit back with exactly they were asking for.
And API is much more profitable (relatively) than subscribers for them.