Eh, I'm not sure we want to go down that road either, but it's an interesting thought experiment. If you declare that EU visitors are unwelcome and unauthorized, are they violating the law by working around that? I find the idea both horrifying and interesting. So many GDPR fans here seem outraged at sites blocking access to them, which seems an acknowledgement that they want to have their cake and eat it too. What if criminal penalties for attempting such enter the mix?