Earlier quoted context omitted.
This was tried some places in the US in the part. Unfortunately most times they failed. Unable to attract enough people, they felt even less alive than the streets and entered a cycle a of death. However there are some signs of a rebirth: https://www.researchgate.net/publication/275887405_American_...
I haven't been to Times Square in a while, but I have to assume that's a good example of a busy pedestrian zone in America.
Maybe it's changed since I've been, though.