The reason Japan doesn't have them on the trains is not because the guards have removed them, it's because they weren't there to begin with.
Here in London, hardly a quaint and sleepy village, everyone uses public transport, including beggars and hoodlums as you put it, and it's fine.
It has nothing to do with "sectors of society".
If you want me on the bus, kick off the dickheads. Making driving worse will not get me on the bus however much you attempt to manipulate me emotionally.
I don't understand your double standard, you should apply the same rules for driving and public transits.
Nope in a waymo I don’t have to smell piss snell, get begged at, have a crackhead grab my girlfriend’s hair, have another crackhead leer at my female friend, have another crackhead catcall my female friend, etc etc etc
Their examples of undesirables are about behaviors, not sectors of society.
Since we're using Japan as an example, Japan does have very strict social rules on public behavior that probably help in this area.