Germany's passenger rail is notoriously failing. China is big and empty compared to Switzerland so there's lots of room to build. Japan's population is stagnant, and so train use might be stagnant too. (No idea about Taiwan.)

What does it have to do with they way they have to manage way higher population density? Singapore is 2/3 Swiss population on 1/3 of the Canton of Vaud.. They are 18 Chinese cities with a population over 10 million.