The biggest challenge for this is the risk of cars. Many suburbs don’t have sidewalks, and the sprawl often means a substantial walk. That leads to an arms race

The biggest challenge for this is the risk of cars. Many suburbs don’t have sidewalks, and the sprawl often means a substantial walk. That leads to an arms race of sorts: people who think it’s too dangerous drive, making it more dangerous for everyone else and conditioning everyone to think a distance greater than the walk from the parking lot is an unreasonable level of physical exertion. Given that cars are a leading cause of death for children past age 5, I can’t completely blame the parents for this, either – poor design is a societal failure and they’re mostly responding to the incentives set up half a century ago.