Ideas have consequences. A subset of ideas — we’ll call it ideology — has consequences on material life. Naturally, this means that ideology is subject to a selective pressure.
Which means we need to consider slack. Just as with intermediary adaptions in the stylized case of eyespots, there can are frictions associated with adhering to new ideology. In departing from the previous paradigm, one is supported by less wisdom and has a narrower reference class to work from. There will be bumps along the way as you and your fellow innovators figure things out. These frictions require slack.
In a world with too little slack, activation energy is too scarce to spend on innovation. If eyespots cost energy but only payoff after the system settles into a new equilibrium, they won’t reach fixation in a population of energy-constrained worms. If one day a Russian serf had come up with Progressive Belief X that could yield some utility returns in a decade’s time if the community refactored a bit, it wouldn’t matter. They have mouths to feed right now.
On the other hand, if there’s too much slack, the adaption will also fail to reach fixation. Why? Well, even if it happened to do so, by a stroke of luck, it’d be helpless to prevent another adaption from replacing it. Too much slack means too little selective pressure, which means that there’s no mechanism by which any phenotype could characterize an evolutionarily stable equilibrium. In a lab where worms are fed no matter what, eyespots might arise and then fade back away, just as might the latest Western social fad among the bored and comfortable Russian elite.
In order for good adaptions to reach fixation, you need some slack, but not too much. When these conditions don’t hold, you might expect dysfunction.
What does this look like? Take education. The poor have little slack, so they under-educate themselves. There are scores of people with 145+ IQs working manual jobs. Whereas the middle class have some slack, so they get roughly the education they need — you see the greatest dispersion in middle class schools, with a sizable proportion not going to college and some going to very prestigious colleges. With the upper class, almost all go to good schools, and most are simply not equal to the education and eventual career they hold onto. They’re able to hold onto their jobs by dint of their good social networks (slack), and so the costs are mostly passed off to society in the form of an elite that is 2/3 incompetent and stupid.
Anecdotally, it seems that this does incur a real cost for these overeducated elites — because they're not smart enough to do the job right, they either become (secretly self-acknowledged) frauds or struggle mightily to keep their heads above water, making a job that would be fun for the right person into a stress fest for them. Both tails don't find work that matches their skills and generates flow; the middle generally does.
More controversially, one might look at something like sexual behavior. But, that’s a story for another time. The takeaway: the sanity waterline is probably higher with the middle class. Whenever you wish to seek wisdom, seek it there first.