What infrastructure do you think is the most communist? Human centered? Industry centered? Something else? What needs to be transformed in modern capitalist society to get to that point? And, most importantly, why are trains so awesome?
I personally think the communist city is not as centralized, instead spread out over the world in mid rise multi family blocks surrounded by farms (as common property using local crops along with whatever a citizen may want to grow should they acquire the seeds and means to care for them) and automated industry running on clean energy like fusion. I think the decentralization of the city re-enforces the masses and communism as whole. This, I think, also doesn’t really need cars. Once the city is totalizing and fully realized it would be a failure of infrastructure to not have easy and reliable public transportation like rail.