I agree, and I think part of the answer is to have access to unmanaged (or very lightly managed) land. For a kid, a wildflower meadow is a thing of wonder. Related, how many US states have a "right to roam" ?
I don't think right to roam is encoded in law like it is in some European countries but it was common behavior in the 1970s growing up. Much less so in the 21st century.
