The issue becomes far more pronounced if the state is able to determine your identity through your phone number, which in Germany is usually tightly coupled to your identity.
I don't need 3rd rate officials being in a position to judge my communication for some badly defined security benefit that allegedly would manifest for the whole society.
Plus Germany still has quite a bad record here. After WWII it didn't stop to invent new forms of totalitarianism through surveillance.
That many warrant aren't worth the paper they are written on is a different issue.