You could geoblock the EU?

If we think of this as import/export it suddenly becomes more obvious - when importing or exporting physical goods from the EU, you have to follow EU law even if you're a non-national with no say in it.

(The example of US extraterritorialism I have is the other way round: https://en.wikipedia.org/wiki/United_States_v._Elcom_Ltd. ; as it says there, "it involved an individual being prosecuted for activities that were fully legal in the country where they occurred")