I don’t think it’s luck. Look at the Andy Griffith show for a glimpse of how children used to be treated close to a century ago. Look at small villages in many parts of the world. Children are basically given free reign to go and do what they want outside of specific times (school and nighttime).

When you give a child freedom, they generally explore, learn, and exercise. Sometimes they do stupid things, but I’d be surprised if heavily structured days for children is good for children.