Indeed, it could lead to cars slowing down and who could want that in Autoland germany.

Just next street, 6 years ago, some guys painted a Zebrastreifen, and got charged for Serious interference with road traffic: https://www.dnn.de/lokales/dresden/falscher-zebrastreifen-in...

(do note that "serious" or "schwer" (lit. heavy) is a qualifier in german law, that increases the charges significantly. The serious part here is that it isn't some alteration that can be immediately removed (e.g. a traffic cone))

Update on that other situation in the district of Neustadt that you mentioned: The city actually just completed a legal crosswalk there, just last week. Here's the article by our public broadcast: https://www.mdr.de/nachrichten/sachsen/dresden/dresden-radeb...