Great observations here. I'll propose a different theory, As a father and as someone who observes these behaviors in both my nieces and nephews and my wife's family. Kids are much more aware of the reason "why" now a days (or at least they think they are!). Therefore, they don't do things just to do them much like we did. Fun was a feeling when I was a child. To a kid in today's world, fun is fulfillment of a purpose. Perfect example is college sports, the college athlete of 2010 is night and day to that of 2022. I am close to the "athlete" world of coaches, and ask any coach and they will tell you the one difference is the kids now want to know WHY...why are we running?, why do we need to practice passing 100 times instead of 108.3 times?, why would the slower player be starting over the faster one?, etc etc. They don't let you lead them down a path blindly.
So, going back to pinball, I think your comment "what am I supposed to do"! is everything in a nutshell. The kids won't just start banging away at a pinball machine or video game. Why "figure something out" when someone has already done it. Most video game players watch YouTube videos before they even boot the game up the first time. They want to understand what success looks like, so then they can go strive for it, or even furthermore plan for it in their own way. The way kids brains work now adays, seems to have a much harder time having "fun" without accomplishment or winning something. Banging things around doesn't work for them.
To be honset, Stern might have a stroke of genius with Insider Connect, bringing the younger crowd along. They can give them "brownie points" for every little thing they do on the machine.