The biggest 2 issues (at least for non-EU companies) are the extraterritorial reach, and the absurd maximum fines that can indeed be assessed for a first, single violation. Whether or not that is the public's understanding of the law, that is how it is written, and when it comes to enforcement, the letter of the law is the only thing that matters.
So we have a foreign government (to us) that has asserted authority to reach beyond its borders and into our pockets with an absurdly complex regulation, where a single violation would financially destroy the company. Since I don't have $20 million to give to them, and the families of my employees depend on their income for things like food and housing, I have to either carry expensive liability insurance to protect against that, or block EU traffic. For us, and I suspect most other sites on the planet, that's an easy decision to make. I'll take a 5%-10% hit in revenue from the loss of EU traffic and be able to sleep at night knowing that someone in a country I've never been to isn't out there filing documents that have the ability to destroy my and my employees' livelihoods.
I won't go into the minutiae of why it's so easy to violate and why most of the experts we have spoken to agree that being compliant is an uncertain endeavor at best, even if you want to comply, because that would be a very long winded comment. But if you do a Google search, you'll see the gist of the problems.