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.)
Not everyone wants to live in a Chinese style mega city.
Fwiw I am a foreigner in Switzerland (I live in Zürich) and I can definitely understand why the people of Switzerland don’t want it more crowded.
Japan's number of tourists has famously exploded over the last decade, and they take trains more than the resident population.