>My dream is that one day most streets in Manhattan will be closed to car traffic and replaced with green space full of trees, flowers, children playing, and usable public space.

This is the hypothetical that GP responded to by saying it's not realistic...so you're acting like he was the one who constructed a straw man argument when he was making a reasonable point directly relevant to what another poster said.

If there's any hysteria in this conversation it's from your unreasonable response.

Actually, where it can work, London may restrict a new development to having a certain proportion of its materials delivered by rail or water.

This might require restoring or even constructing a jetty or small siding. Any cost is balanced against the disruption and danger of taking many large vehicles through residential areas.