I&#x27;ve observed the same but interpret it differently.<p>Life gets more differentiated as you get older.  You learn what makes you happy and what doesn&#x27;t, you experience different situations and react to them, and you make decisions about who you&#x27;re going to be and what you&#x27;re going to do.  And all of that becomes part of your identity.  It&#x27;s part of your accumulated self-knowledge.<p>And part of that is perceiving differences in how you see the world vs. how other people see the world.<p>A banker, a janitor, a nurse, an engineer, and a dropout can all still be friends <i>if they have something in common, and confine their friendship to that thing</i>.  I still occasionally get together with my high-school friends, when I happen to be back home, and we&#x27;ve become bankers, janitors, nurses, engineers, and dropouts.  But 15 years after graduation, the high school we went to is an increasingly small part of our identities.  And it feels constraining to hang out all the time, like you&#x27;re denying all the other parts of yourself that you&#x27;ve discovered since.  It&#x27;s great to get together for a weekend and reminisce about old times, but it&#x27;s not something I&#x27;d want to do <i>every</i> weekend.<p>The economic aspects are second-order effects.  Yes, this tends to stratify people into economic tiers.  But the reason for that is that it&#x27;s hard to do anything for a significant portion of your life without it becoming part of your identity, and it&#x27;s hard for a skillset to pay off without doing it for a significant portion of your life.  And different skillsets are compensated wildly differently, based on supply &amp; demand.