I think it’s a bit more complicated than that. The EU law will need to be implemented by national laws and at least in Germany, there is Art 10 GG (the 10th par

I think it’s a bit more complicated than that. The EU law will need to be implemented by national laws and at least in Germany, there is Art 10 GG (the 10th paragraph of the constitution) which protects one’s rights to private communication (specifically also against the government; this is the whole point of constitutions!). Granted, the paragraph also contains a provision for lawful exceptions, but in general, our highest court has ruled that such exceptions need to be reasonable in scope. I have some hope (but less than I’d like) that this will happen here, as well.