But they haven't actually dealt with it. This is a common misunderstanding among websites that do this.
EU citizens are not required to identify themselves to you preemptively for GDPR to apply. If I connect to their website via a US VPN and they start tracking me without asking my consent assuming I'm from the US, that's a violation of GDPR.
So, in reality, there are two cases here:
1. They do not operate under EU jurisdiction, and thus might as well not have bothered making the EU specific page since the EU has no leverage over them any more than china can force them to take down articles that paint the chinese government in a negative light.
2. They do operate under EU jurisdiction, in which case their EU specific website is not in and of itself enough to handle their GDPR liability. Regardless on your opinion on VPNs, they must still for example nominate a specific data protection officer if they fall under EU jurisdiction.
I suspect that at least some of the websites with EU specific experiences know that the EU experience legally speaking doesn't achieve anything and are attempting to use them as a protest movement disguised as a self-righteous compliance effort. A whole bunch of other websites then didn't do their homework and are blindly hopping on the bandwagon.
The funny thing is the whole thing is backfiring, since a common reaction is "the EU experience is really nice I wish it was like this for americans as well".
