On the contrary, if you are running a business where 99% of your customers are outside of the EU, its totally rational versus opening yourself up to massive liability.
If the customer joins your Japanese site while in Japan, its governed under Japanese law, not EU law. Your citizenship is irrelevant.
You need to comply with the laws of the jurisdiction you operate in. If you don't operate in the EU (and having a presence on a global communication network does not qualify), EU laws are not applicable.
The onus is on concerned EU citizens to stick to .eu domains with a feel-good GDPR-VERIFIED banner if they are so inclined, not on the rest of the world to bend over.
As a non-EU business, I will pay my GDPR "fines" right after I'm done paying my Iran and North Korea issued fines. Cheers!
Seriously though, I made no comment on the law itself so I'm not sure what your point is. Most reasonable people would agree it's a good law in spirit, and I wish I had some of those protections where I live.
But the notion that it can be enforced on non-EU entities is ludicrous.