Who is getting their fair share of the space available?
In the beginning was the path. It was undifferentiated, shared by people and animals alike, and eventually wheeled vehicles pulled by humans and animals. While dating the First Path is impossible — the very first First Path must have been a path that was reused once, and slightly better than the unimproved space around it — it operated both in early settlements and on routes connecting nearby settlements.
Today’s version of that is the sidewalk or footpath. It is now used for people walking, sometimes for people moving goods, and occasionally for people on scooters and bicycles. It should not be used for storing cars, though it is. New uses will include low speed delivery robots, as shown in the photo from Starship.
When we see a raised crosswalk, we know the First Path is given the pre-eminance its venerable status warrants. When we see shared spaces, we know those harken back to the early undifferentiated path-spaces of earlier centuries. When we see pedestrian-only zones, we see a First Path that has grown up.