Forget all the stuff out there that says the GDPR protects EU citizens. This is a question of jurisdiction and enforcement. Say I run a blog under a business registered in the US funded by advertisers in the US. A EU citizen that comments on posts issues a GDPR request that I ignore. Their government fines me. I tell them to get bent, I am out of their jurisdiction. What can they do at that point?
“You read that condescension into it by yourself. You are asking a question and that is the answer I have no idea about your context.” That is fair. I hadn’t had my coffee and have been dealing with an unusually high amount of unpleasant individuals lately, hence the short fuse.