> to just walk/bike out of the town or city they live in to play and have adventures in the fields and parks and maybe a little bit of thornier wilderness around them, all on their own, for hours at a time. A.K.A. "just be home for dinner."

It sounds like you've never been to Japan. It's exactly like that here.

>I think the countries I've visited have all been Commonwealth or ex-Commonwealth nations. Maybe that's the common factor?

I feel like the Anglophone nations have all been following America's lead in many ways.