That's a pretty incomplete view of how jurisdiction works. You do probably need a US court ruling to enforce a claim against a US entity – but if that entity has any EU subsidiaries or assets, you can bet that European courts will come after those.
> Blocking for security is another thing. Maybe a good idea, maybe not - but that's another story.
As a customer/taxpayer that needs access to a service from abroad, I really don't care why I have to jump through hoops to cancel a subscription/order or pay my taxes owed.
I am not sure you read my post in details - I explicitly mentioned that I am talking about local services, without any international footprint. And mentioned that in case of this footprint - yes, they will be sought after.
This is also exactly waht the US does to enforce their "extraterritoriality"
And they can be enforced not only from assets, but also from travel or various financial tools at their disposal. (it would be surprising, but for many businesses, it's not worth the hassle)
The golden days of global network accessibility are closing little by little.
They can tell whatever they want, but it would need to be a US court (in that case) who would do the litigation. Which they won't.
> The US does do that kind of thing though. As a dev, break some law, step foot in the US for a conference, get arrested
yes, this is why I mentioned that my point is only for local businesses. Travel or business in the EU can/will be problematic.
> Heck, I was in Mexico and I couldn't login to my provincial government tax portal. There are constant security issues with those sites.
Blocking for security is another thing. Maybe a good idea, maybe not - but that's another story.