If you live east of the Anacostia in DC then yeah, the kids aren't as safe outside on their own, but that's more from a gang recruitment angle than a traditional "stranger danger".
Obviously people who live in crime ridden ghettos can't be quite as free as people who live in safe neighborhoods, and it's something we should fix in the long term, but it doesn't mean we should punish those people who live in safe areas with overly restrictive laws that hurt their children's development.
It's kind of sad that the kids who are already disadvantaged by being poor, having failing schools, and likely only a single parent are also the ones who don't get to be free and learn independence as children. It's yet another cog on the cycle of poverty.