"Unter dem Stichwort Vorratsdatenspeicherung werden solche Daten speziell für Repressionszwecke gespeichert. Sie ist derzeit ausgesetzt, die Verkehrsdatenabfrage als solche bleibt aber in Kraft."
The data detention is "currently suspended" according to your own link... sigh.
You did not address the distinction between the police/intelligence agencies having access to the data providers collect and keep, unfortunately but mostly voluntarily -- and the EU data detention directive, which Germany only implemented for a short while and is now in gridlock about, and which would force the providers to keep that stuff around, wether they want to or not.
I mean, if it's all the same, what is the fuss about? You did not answer that. Just because it is still bad, doesn't mean it's all the same, and that accepting and implementing the EU directive would make no difference.