Toward the end of our (X) childhood, a number of major transitions in the handling of kids were being made:
Playgrounds were being transitioned into minimally-dangerous versions of themselves
Bullying was being cracked down on
Latchkey parenting was being recategorized as neglect and being cracked down on my CPS
This meant that Gen X kids had a lot of situations to deal with as kids where they had to develop physical skill as a means of staying safe.
For example by the age of 7 I could climb a tree and be pretty safe because I had developed upper, lower, and trunk body strength, awareness of how strong a branch is and how to test it for strength, how to detect when a contact point I was resting on was slipping, and how to control my mind enough to maintain enough focus to not slip up while climbing.
On playground equipment, I had to be ready for a fall onto concrete, and I had to know when wood was likely to produce enormous splinters (I actually got a huge splinter through my ass once. It went in below my butt cheek and came out above it), and I had to deal with the results of kids going crazy trying to spin the spinny thing as fast as they could. I went flying off that thing so many times.
Also, during the summer when I was 7, my friend was 8, and we had little bikes, and we would spend the entire day outside wandering the town. We often would find a stream and slowly work our way up the stream. This involved a lot of balancing on rocks and logs, catching small animals, even fighting my friend sometimes. We'd swim in muddy streams that were full of broken machinery and glass bottles, and it was up to us to know how to stay safe in that environment.
The world was just less safetyfied back then.
Now I see people of age 20 or so, and they walk like toddlers. I'm not talking about disabled people here. Just people who are able-bodied, but they move like they've been recently downloaded into a human body, like it's unfamiliar to them.