> Does anyone know of anywhere that managed to bootstrap good public transit after the fact?
Central Tokyo (inside Yamanote line) has almost no national railway lines (just one/two called Chuo between Shinjuku and Tokyo station). Most of its subways are inside central Tokyo. The second subway line didn't open until 1954. Tokyo is much later to build than London, Paris, or New York. I also think that Seoul started building trains very late.
Tokyo was burned to the ground though just before that started. [https://en.m.wikipedia.org/wiki/Bombing_of_Tokyo]
It also wasn’t really a major city historically over the types of timeframes as London, Paris, or even New York.
Modern Tokyo is more of a ‘new’ city, and the subways were constructed along with a lot of the new construction - that central Tokyo was almost completely destroyed in the war certainly removed the friction that would otherwise have made that hard, eh?