Traveling below speed limits makes this even worse because majority of the cars on the road will actual try to pass you, whereas if you traveled or slightly above speed limit, you would be moving with the traffic with less "passing" occurring.
So the answer is to raise speed limits and raise minimum speeds. But no matter what the speed limit is, people will always set their cruise on a couple miles higher. I frequently travel on I-93 north of Concord where the speed limit is 70. At 70 I only pass vehicles that are entering or exiting, or maybe a truck on a hill, but I am passed frequently.
Oh, about Germany, do they have deer and moose that wander onto the highway? I fear animals more than other drivers, regardless of their speed. Deer can spring out of the brush and onto the highway in an instant. Moose move slower but unless there's snow for a backdrop they are invisible at night, so half the year your headlights will only tell you how many feet you have left to live a normal life, or live at all.
Hit a deer = wreck your car.
Hit a moose = wreck your life.
For further reading: https://newengland.com/today/living/...ake-for-moose/
PS, I wonder if driverless cars can compensate for animals on the run, or can compensate for over-riding headlights?