Palantir would have formed the core of both the Gestapo's and the STASI's population-monitoring programs, and perhaps Germany has had enough of that kind of thing?
The judgements footed on various articles of our moder (post 1945) constitution and its bill of rights and indirectly in the experiences under NSDAP and SED rule.
This is the key. Germany doesn't have a central citizen database or something like that, but each municipality has a system on their own. Any bad actor can't search through that to discriminate, deport or whatever people. This of course also leads to problems like paying out corona support money to students still isn't completely done etc.
Palantir tries to create an Über-Database.