I've driven pretty much everywhere in Germany except Bavaria and I've never experienced a horror show such as @DeadlineX described or what I regularly see in dash cam footage.
I may need to get a dash cam myself though to collect proper evidence of German driving behavior.
In my experience the worst drivers are from Hanover and would be interested if anyone can confirm or deny that.

To properly encourage appropriate driving speed proper road design is needed.
On a highway in the Czech Republic for instance I've noticed that the lane dividing markings are shorter and closer together between the first and second lane which made it easy to drive the 130km/h limit without looking at the speedometer because the sense of speed was greatly increased while on the highway in Germany I feel quite comfortable at 200km/h while at 130km/h I feel like a snail barely moving forward.