What changed from when kids played outside from dawn to dusk?
My own childhood community in Bloomfield was then a well-established one composed of descendants of Irish and Italian immigrants, many of us going to the same church on Sunday. There were a few baseline expectations shared by the community about how children should behave in people's yards or in the streets. People could talk to each other from some shared moral premises.
But today those communities seem rarer, and so, too, those shared premises about how kids should behave. More than that, there's a fear of taking responsibility for kids in the neighborhood. Deliver a short report on a child's behavior and his parents may snap back, "Don't tell me how to parent my child." A neighbor's interest may seem invasive or even creepy.