I think part of it is desperation. There is absolutely nothing the EU can say that will convince the American politicians that privacy and corporations are out of control in the US. Americans might believe it's fine, but Germans are careful about how personal data is handled and who has access to it.
Culturally the US and Europe is drifting further apart and from the European side it's very hard to see that the US isn't wrong.
Culturally the US and Europe is drifting further apart and from the European side it's very hard to see that the US isn't wrong.