I'll have to disagree, and not because the older generations were "tougher" or "more resourceful". But simply because the percentage of people that live in rural compared to suburban or especially urban environments. Well a few more reasons, how many kids have access to woodlands they can explore now compared to 20 years ago? 30? 50? And yes I'm going to go there, electronics. When I was a kid pong was the hottest thing, then came Atari.
Where I grew up was suburban, but a block/block and a half a way there was forest, swamp, lake I could access to explore. Now closest would be 5 miles at least and you have to stay on the trails. No access to those that you can just wander now for at least 20-30 miles. In regards to fire, I can use a lighter, matches, ferro rod, magnifying glass, and once used a flint and steel. Never started one by rubbing two boy scouts together though.
I saw a report a couple years back that kind of explains it. Take a deep rural kid and drop them in the middle of Indy or Cago. How will they respond? Take a urban kid and drop em in the woods it will be about the same.
Growing up there were zero electronics. TV's and radio's yes but I was a teen when Capt. Kirk (no relation to Freemen) 1st opened his hand held communicator and talked to the star ship. We camped (no electricity...tent camping) and spent a lot of time on the Family farm Yes, lots of wooded areas and creeks ponds and the like. It was a great way to grow up.
I have tried to expose my kids to all of this but as you said, it is getting harder to find the ground to wonder freely. We have access but all are well over an hour out and most are 2 hours plus.
The survival skills I have shared with them I believe will get them through most SHTF scenarios.
Sad thing is I do not see them doing anything with their kids along these lines.
All we can do is all we can do.