Earlier quoted context omitted.
In my prewar non-car-centric city, kids still walk to school. They don't play outside like previous generations. You'll see the Christmas bikes for a few weeks when it's warm enough in late spring then nothing all summer long.
As a parent, I can tell you video games and smart phones have a lot to do with this.
Even back then kids weren't clamoring to play outside in the street. Or ride bikes etc (there was a clique at school who were skateboarders but not a widespread thing). I think it very much depends on the kids temperament, my experience as a kid didn't involve a lot of outdoors activities.
However my parents were pretty big on making sure I had exercise I played sport on the weekend (cricket in the summer and soccer in the winter) and it was non-negotiable my parents insisted on it. If not for sport I don't think I'd have spent any time outdoors at all.
I think Weekend Sport might be an Australian cultural thing does the US have weekend kids sports?