No, it's you. I'm 43 and while I don't see myself as particularly nostalgic either, I have plenty of colleagues who are. I have no idea how we compare to general population.
Just yesterday I competed in the open division of a regional racquetball tournament and in a month in a half I'll compete in the open division in a regional powerlifting meet. The is not a humble-brag as much as to contrast this to the vast majority of the folks my age with whom I hang out.
Moreover, I'm heavily invested in growing intellectually which seems a contrast to many of my peers.
These folks have largely, though not all of them, adopted the "I'm too old" mentality to try to compete or grow in athletics or in intellectual pursuits.
The point is that this article, I believe, tends to comport with reality: many people begin to accept an easing of their personal standards and drive for growth because they're "too old" to not continue to push and compete.
Maybe your peers never really had the personal standards you thought they had in the first place, and simply stopped trying once the peer pressure eased up and they got a good excuse to lay around?
This type of pressure is often met with scorn as something we are too good for. In my case however, it really helped me become a better version of myself over time.
I am still making things, it's just more difficult now.
But video games are a hell of a lot better now than they were back then. Legend of Zelda: Breath of the Wild? The Witness? Life is Strange? Persona 5? So, so good. And there's nothing stopping me from playing the old games when I feel like it (except having the time).
Also I wouldn't mind having another replay of my high school and college years with the confidence that I have now. A lot of my experiences with women would have gone a lot more positively then if my attitude and approach then were the same as it is now (Well, in the past five years. I'm in a solid relationship now). I wouldn't want to replay the sitting around a classroom or schoolwork part of it though.