Having a diagnosis also gives you a set of tools to actively deal with your issues. Personally I have trouble with avoidant personality disorder, and I really wish I had gotten diagnosed earlier. Maybe school and my early career would not have been such a dumpster fire if I understood how to properly deal with myself back then.
So I think there's lots of examples of diagnosis's helping individuals, my specific concern is why it is if all this diagnosis is apparently just helping everybody, why is the general population getting more mentally sick over time? I can think of only two reasons -
1: That the mental health system is actively harmful at the population level.
or
2: That the mental health system is impotent to address mental health issues (more keen on this idea honestly, but I can't even rule out 1)
The latter case means that the mental health system could be helping, but at the very least, the mental health system is a distraction from the bigger issue of mental health. I believe declines in mental health are driven by things like increasing inequality, scarcity, competitiveness, loneliness, and so on which we can't nessecarily solve by telling people you are disordered with such and such so live in such and such a way and you can maybe be better adapted to a society which has their collective mental health in freefall which I dunno is something but it's pretty depressing.
P.S. I specifically resent the label of "disorder" in general and think that label is part of the problem, because no matter how you spin it, somebody saying you are "disordered" is an insult, and as we call more and more of the population disordered I think the adjective will become untenable to keep using. I'm more keen on the concept of neurotypes, because neurotypes CAN be negative, and CAN require accommodation, and CAN require treatment, but none of those things are NECESSARILY true becuase "neurotype" isn't loaded in the same way "disorder" is. If you discover your "neurotype" you can try tools and techniques that helped others with that same neurotype. Whereas the word "disorder" sort of has an intrinsically negative connotation, and I don't think it's medically necessary for psychiatrists to regularly insult their patients.
The mental health system is so condescending and some of the shitty things they do don't really get examined or critically looked at that much. Like why don't we ask, is telling millions of people they are "disordered" likely to improve their mental health and confidence and self-esteem? Probably not and it's totally viable to avoid doing this.
Are there any positive connotations for the personality disorder umbrella? I really struggle to think of any. It's cool that the ASD camp has managed to become "differently neuro'd" or whatever but everybody I have talked to in the PD camp knows we are just subject to different flavors of unhelpful irrationality and not much else.
Except maybe shizoids who can count on being aloof to any bad interaction instead of being uncontrollably dragged around by them, but miss me with the anhedonia thing please.