Car-centered road are not a good biking infrastructure, as cyclist don't feel safe on them, and only a marginal part of the population is willing to cycle when there is no proper cycle infrastructure.
For an example of cities actively encouraging bicycles, go see in the Netherlands, where they decided in the 50s/60s they actively decided didn't want cities to be car-centric.
You'll see a lot of bicycle-only lanes, segregated from the road. And tiny roads, that force cars to go slow.
A bike lane can be built because of racist motives, yet only a minority of bike lanes are built because of that.
There's also the problem of busy junctions within settlements that are designed around cars. This is another example of where alternative bicycle-centric lanes and signalling are much better suited than the regular road.
While driving culture generally is terrible in Germany, in my opinion, with people driving way to aggressively, the situation may be improving gradually. The idea of having to keep some distance when passing cyclists seems to have reached some drivers. (From court rulings 1.5 meters is the absolute minimum)