The irony of the Japanese example here....
You are right, the Japanese employ enormous numbers of engineers and cleaning crew to make the whole system run like clockwork, usually working at night. And at the same time, the systems themselves contain many automated, advanced components that require little human input.
BUT, and this is where the irony comes in, neither have they stopped manning the trains and stations with surprisingly numerous employees:
- There isn't just a driver, often (in Osaka, for example) there is a guy at the back of the last wagon, checking whether the crowds have got in okay and the doors can close.
- Even though the ticketing systems are mostly automated, long-distance trains still have people going down the length of the train to check, anyway.
- In the big stations you actually have guys standing around waiting for every train to arrive, apparently doing little more than keeping an eye on things and calling around information.
- Finally, in Tokyo occasionallly you still have those silk-gloved attendants who literally push the crowds into the trains during rush hour.
In short, to the Japanese, highly advanced public transport still needs numerous human employees in order to provide the best possible experience to the travellers. They value both the engineering AND the human presence. This is by far the best philosophy, IMO, but it's not the cheapest approach obviously.