I don't think it's really comparable - as the rules at play here are designed to protect the privacy of EU persons. There are plenty of things that I could buy

I don't think it's really comparable - as the rules at play here are designed to protect the privacy of EU persons. There are plenty of things that I could buy from parts of the US that are considered unsafe in the EU for example, and so it is forbidden for me to engage in trade and get them. They would (theoretically) be confiscated at a border. Despite some politicians best efforts and desires, there's no practical way to stop someone 'importing' privacy damaging web traffic, so the risk of non-compliance is being loaded onto foreign website operators. Therefore should a US website desire to follow EU laws, there would be no restriction on them being accessible to EU people.