Earlier quoted context omitted.
Why do you think experiences are limited to mid twenties? What kind of experiences are you talking about
Probably parties, concerts, impromptu weekend trips, paying to crawl through mud for five miles, side hustles, short term relationships, and the drama involved with any of those. That stuff tends to die way down for most people in their 30s.
It's not that we don't do these things after 30 or even 40, it's how we do them (hint: more means, wiser/less stupid about it 'cause been there, done that).
Now there's a historic truth to the cliche, but let's not pretend this is 1960 still, not even 1990. As we near the 2020's, socially everybody may work (M+F), everybody may change diapers, everybody may get drunk/high even after 40. It's not frowned upon anymore to just live, so what do you know, people just go on about living their lives, whether in their twenties, thirties, eighties... "Living" includes drama, it's just the nature of it, and there's this kid inside all of us --but as you age you're just so much better at handling said drama, and turn it into no less memorable but much more comfortable stories.
Most incredible nights of my life? Twenties for sure, even late teens. But best nights? On average it's not even funny to compare: at 34 it's so much easier to feel good with oneself and with the world. Which makes me actually much more daring personally, with work (and outside-the-box thinking), with relationships (and quirks), with my very own self.
Just to widen the perspective beyond my own anecdotal experience, I wonder: why this change between 20th century and 21st century societies? You see, when you read people from some 2,000 years ago, you quickly realize that they shared the same thoughts, the same feelings, the same life stories. Funny people back then would probably be funny today, and you could hear Romans complaining about foreigners taking their jobs and changing their culture... The human being part of the equation didn't change.
What changed is organization, and that's a long talk but essentially I feel that as we gained freedom on an individual basis, we need less "general principles" to guide otherwise clueless peoples --and this is currently still changing fast as even the perimeter/mission of the state and governments is very much in question, from corporate/money influence over citizenry, to wiki and other leaks, passing by individual rights. On the other hand, we begin to observe what the human race really is like, how it behaves, when given the freedom to set its own way (at least in the western part of the world, but surely these days "social progress" is happening everywhere regardless of political/economic freedom).
It's 11:30 and I am now going to resume work after this early morning coffee. :}