I'm curious about this, too. I once commented that, say, my hobby website isn't subject to the GDPR because I love, work, and play in the US and that's where my blog is, too. Turns out some people have
very strong opinions about this and insisted that I
am subject to the GDPR. But as a practical matter, how? I don't have a presence outside the US. Even if I violated a EU law, is there a reason I'd ever need to care? For instance, I know I've violated some Chinese laws by criticizing their government, but I'm OK with that because, really, what are they going to do about it?
As an aside, I'm completely behind GDPR, CCPA, and related privacy laws. I think they're great. I definitely comply with the spirit of the laws in my hobby projects by doing things like not tracking anonymous users, not retaining identifiable logs, etc. This isn't me trying to get away with something nefarious. More like, I don't (and won't) bother with things like cookie banners even if GDPR would want me to.