I don't think it is a generational issue, or correlated to age at all. It's not necessarily driven by social class either. My guess is, it must be a societal trend. We've forgotten the value of getting our hands dirty. This statement is in no way, amply supported; my gut feelings will have to suffice.
When my sister and I were little, we played outside nearly every single day. We had a world of make believe at our fingertips. To this day, a walk around the block brings back vivid memories. Torn jeans, muddy sneakers, and runny noses were indicators of a good day indeed. Capture the flag, running bases, and tag filled the warmer months. Building forts in the snow and sledding marked the winter ones. We were always moving, always exploring.
My parents talk of similar childhoods. Dad didn't have a lot of toys so he had to work with what he had, or "borrow" things from his cousins. Miraculously, they still talk to him. They all lived together in a two family home, where I happen to live today. If I close my eyes, I can invision them playing together and growing up between these walls. A few towns over, my Mom was living simillarly. She and her friends played house together, pairing off to make imaginary couples and wandering around Grace Avenue. They played games and made things with their hands.
As adults, we don't have the same opportunities to play with wreckless abandon, although we can certainly channel our youth if we try. My papa is living proof that youth is a state of mind, not necessarily represented by your age. Gosh, I hope I stay half as cool as he is. Papa gets his hands dirty. He tinkers in the garage, teaches himself how to make different kinds of nautical knots, gardens, and builds. Maybe this is why he stays so young.
Dad works like no one else I know, and thankfully he instilled his views along the way. When I was old enough to work the power mower, he took me landscaping on weekends. If I was way thinner, I would be Jessica Biel in Summer Catch. Although it would seem totally unenjoyable, it is ( I still landscape now and then) and always was oddly rewarding. Dad says it builds character, and I whole-heartedly agree. To exert yourself and labor a little isn't like jumping in puddles or playing tag as a kid. But it's similar in the regard that there is a level of motor stimulation that triggers good feelings in the brain. There is evidentiary support of that... so there you have it.
Things come really easy in the modern age. I am immensely grateful for the ease with which we can access information, communicate, and experience our surroundings. Strides made in technology and the sciences are awe-inspiring. Sometimes though, I fear we are complicating the formula for happiness. A patch of pavement and some chalk was sufficient to occupy us for hours when we were young. And obviously, there were no tablets but we made it ok. Kids should play outside, and get dirty.
As for me, there's always grass to be cut.