I'm the author of the post, and yes: blocking 500 million geolocated people is crazy. That's not the spirit of the law.
I just wrote the post because if you want to overkill and you are lazy, you can follow our recipe to 'implement' GDPR. I just wanted to be sarcastic and also show how easy to implement Cloudworkers + Apility.io.
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.
You should consider making this a bit clearer in the beginning. There is already a lot confusion about GDPR lately and people could take your post seriously. As pointed out by others already, geo-blocking isn’t a proper way to become GDPR compliant.