It is very possible to live in every German city without a car. The problem is not trying, but that any changes to the street layout, which slows down a car is going to be challenged in court. Unless the city can show that this was completely unavoidable. Unless that is changed, you just can not do much about it. Btw anybody can sue, if it hurts a car, but if you cause problems for anybody else like cyclists or pedestrians, you have to prove that you actually are impacted by the changes. So pro pedestrian and cyclists organizations unlike pro car associations can not sue the city, to fix illegal street layouts, which are common.

That being said, you usually do not go to the bad parts of a city, while on vaccation. Spain has some extremely car brained infrastructure as well.