And while Germany is probably a bit worse than European average, I have seen plenty of other similarly car-pilled places in Europe. Though also some positive examples. Paris has done a lot to bring some parks to a horribly car-infested city. Amsterdam is great. Rome is pretty decent. Few places in Europe are as bad as the US when it comes to car-dependence. But there are also very few places comparable to Japan's approach to car ownership
Highways are great when everyone has a different path.
Japan has most (but not all) of its large destinations on the pacific coast, which works great for rail.
I'm sure passenger rail networks used to have more routing options than amtrak does now, but it's hard to get between a lot of places by rail without going through Chicago. In the western US, you can go north/south in the pacific states or near the missisipi. Sure mountains are hard to cross, but there's no north/south in the plains either... Or Atlanta to Florida, etc.
With small airports, there's probably plenty of flight time is worse than drive time and security and rental counter time add up too, so flying isn't always less time than any other mode, but often it is.
Europe shifts people by train, not freight.
The US/Canada/Mexico is about 10% more than the EU, but it shifts 7 times as much freight by rail.
I tihnk that helps explain the feasiability of train on each country more than inherent choices
A sparse railway system would leave parts of the country less populated by design as it’s simply harder to get to them. People would bunch up into cities and towns because they had to.