I'm well aware that there are multiple options for public transport, but none of them are actually as flexible or as far reaching as cars/taxis. To me this 'but why not trains' on every article about self-driving cars is a tired meme that fails to address that these are not equivalent options. I might as well say "Well, why don't we get rid of these expensive rails and fixed timetables and just lay down some cheap concrete and let people navigate how they want" in just as condescending a tone and be equally as unconvincing.