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?
Based on your replies to other comments, it seems you don’t see how the GDPR, or GDPR fines, could have any effect on US companies.
https://www.enforcementtracker.com/
Sort the list by fines, and you find US companies paying whopping amounts. Many affect their EU presence (such as Meta Platforms Ireland Limited), but others don’t (such as Meta Platforms, Inc.).
Ask yourself if these giants were just too nice to give in, or if they were too poor to hire a lawyer.
If you think both options are unrealistic, maybe the GDPR does have an effect even on US companies.
I think the largest assumption you are making is that the OP does business with the EU. If they do not, they are truly out of the jurisdiction of GDPR and wouldn’t be finding themselves on that list. Those fines you are referring to a multinational corps that definitely do a lot of business within the EU.