Atlantic Diode again
"This assertion that the regulation can be enforced just because they're [non-EU companies] marketing to European citizens isn't going to happen,"
US regulations seem to be enforceable to non-US companies who market to US citizens, e.g. Canadian on-line gambling sites, UK students who have web-sites with links to TV programs...
If EU regulations are not enforceable to the US then the same should be true in reverse. Either stop the US enforcing their laws on the EU or force the US to abide by EU regulations when dealing with EU citizens...or is this another one of those 'Atlantic Diode' things like the extradition agreement?