Stripe supports 3d secure and has for years. https://stripe.com/en-ca/guides/3d-secure-2

Heh. No it doesn't because they require their users to treat it manually and as a consequence a lot of americans don't.

Example 1 that is definitely going through Stripe: Ars Technica.

Example 2 that I don't know what is going through: Asimov's Magazine.

In the race for no friction, they add friction for EU users.