Hey can they ask their coding agents to support 3D secure, so I can pay with EU emitted credit cards on the few US sites I'm interested in?

That's for the Stripe customer to configure. Stripe itself has supported 3DS since ages ago.

Edit: also you'll find a pretty common sentiment among US website owners is that the new API that supports 3DS is overcomplicated and they want their 7 lines of code create-a-charge-with-a-token back. Screw the Europeans because they only care about US buyers anyway.

Well it's not like I buy many physical goods from US companies (and amazon US is fine, even handles customs for me).

Keeping my subscriptions to Asimov's and Ars Technica is becoming a pain though because ... Stripe I guess. Ars staff even confirmed it.

A Revolut card works fine, local banks' cards deny the charge by default and if you're lucky they call you and ask if they should allow it.