I feel like blocking European users should return a 451 error, "Unavailable for legal reasons"
The only group of websites that I have encountered blocking me are small-town newspapers in the US, mostly the south.
Compliance is almost trivial for a newspaper website that does not ask for any data.
My suspicion, especially considering the regional distribution of these blocks, is that some of these decisions may be driven by politics more than anything. Plus, of course, the possibility that a low-quality rural newspaper can count their European visitors on one hand.