As per them, so long as the mind can segregate experiences as desirable and undesirable, it will continue to crave the desirable ones and reject undesirable ones.
If all the recent experiences are desirable, then there will be further segregation within the desirable ones till the undesirable bucket is again full (and vice versa).
This gels well with anecdotal experiences of craving for something like financial independence only to feel once some one gets it that it is either not sufficient or craving for the opposite happens.
So if we go by these theories, the center will never be reached. The pendulum shall just swing-by from one end to the other with the middle being really short lived.
For the most part, yes, it's called building resilience[1]. The hard part is that people view adversity relative to their own experiences, and don't want to be told that they need to "suck it up" when their ride is a few minutes late, or the waiter got their meal wrong. A coddled person will truly believe that their minor inconveniences are very difficult events, and there isn't a way to force them to build resilience, so they might end up being coddled even more just so they'll be quite.
On the other hand there are people who never recover and are never the same again.
I suspect it will occur when people stop parenting each other and when people stop deliberately concerning themselves with the disagreeable opinions of others (negative attention seeking).
Equivalently, does it mean that if we expose ourselves to macro-harms, we will be immunized against harms lower down the scale? Is the endgame a Spartan, ultra-violent survival of the toughest?
Or is there a point in the middle where the right amount of harm is tolerated, or even encouraged? How will we know when we have reached that point?