I chuckle when my parents generation call my generation spoiled and thin skinned because of things like this and participation medals. They are the ones that made those changes because of their feelings, standing there in fifth place getting a medal felt stupid to me as a kid, it was just so my parents could feel happy about something.
I loved climbing trees as a kid. I try to get my kids to climb trees, but they refuse. I don't see a lot of kids climbing trees at all anymore.
But I don't think the thing that spoiled them are the safe the playgrounds; it's the constant access to computers, tablets, the internet, Youtube, etc. In my day you had to wait until Wednesday or Saturday to get your cartoon fix. Nowadays there's instant gratification and constant passive entertainment. They're not bored anymore, they have no need to be inventive. I suspect that's a bigger problem than safe playgrounds.
People tend to cut the lower limbs off trees in parks for the sake of appearances, and to leave shady areas of lawn underneath. If you want to help kids climb your own trees then you can leave a foot or two of each branch as a handhold and make it easier on them.
Maybe your father showed it to you, when you were small and do not remember it.
But yes, it is leading by example. If other kids climb trees, that is an example as well. If "kids these days" rather play on their devices, but I want my kids to experience something different, then yes, I need to show it to them. (But I also, or mainly do it, because it is fun and training for myself).
If we are with other, wilder kids, which we occasional are, no need to show anything to them. But on the default playground today, it really does seems like it has gotten very rare. A tree is not a certified playelement after all and who to sue if something happens, so best to avoid it, is what most probably think.
Good point. It was the same with me. I climbed trees my entire childhood and never saw my father do it. I doubt my daughter will though as there isn't any forest nearby and in the 90s, kids spent all summer outdoors and that isn't even legal anymore (my parents didn't know where I was for hours at a time when I was as young as 5).