"Everyone has the right to respect for his or her private and family life, home and communications."
On the short term a change to the treaties of the Union is not realistic, in my opinion. So I am afraid we might be stuck with having "to fight over and over again", using the above as a foundation. I guess I think of it as educating the politicians.
Fortunately the pro-privacy voices in the EU seem loud enough. For example, in this case the Belgian national privacy authority had already complained about the proposed law. And Germany seems to have adopted the right to encryption in its latest coalition agreement.