All it takes is a single populist data regulator in one of the EU's twenty-eight members,. Will they win? I don't think so. But in the meantime, you'll be dragged through costly regulatory negotiations. Those negotiations would become much more expensive if one had any European users.
Litigating on this particular issue would be an incredible stretch though. Offends basic sense of fair play imo.
If Turkey gets EU membership, it would be a hoot to see how Erdogan uses this law.
At least litigation has a clear end. The problem is more endless requests for information, each requiring research and drafting by expensive EU lawyers. A burden irrespective of whether you did anything wrong.
One of the EU's twenty-eight members will try to extradite an American executive. That will be shot down by U.S. courts. We'll throw tariffs at each other for a few months until whatever administration that happens under negotiates a compromise.
GDPR only fines and sanctions. Dont hold EU assets and you would be ok.