Which is unlawful if your users are in Europe (and also possibly of they're just from Europe?). You are obliged not to discriminate against users who choose not to be tracked (or whatever).

So, theoretically speaking - because I'm not from the EU - if I choose to not comply with that law, is it my responsibility to figure out a technical manner to block EU users from accessing my content, in this global Internet world?

Do you have a a link? If you're based in the EU I assume so, but the EU doesn't regulate the world. (At least directly, if you comply with GDPR you're likely to port that over to other regions to avoid possible legal issues)