My favourite part of psychiatry is that diagnosis never shrinks, it only grows, and this makes people healthier and the increase in mental illness is just us "discovering" that people were mentally ill all along.
The field is an endless dynamo of medicalization because they serve as a gatekeeper to funding, and if you throw enough money at anybody start to feel better, which creates an incentive for more and more to get diagnosed. For a broad swathe of new people to be diagnosed as mentally ill does not require biological evidence, or even proof that the classification improves patient outcomes, it just requires abusing the criteria used in broad all-encompassing intrinsically political typologies (Like DSM-V) until you can hammer most of the population into the mentally ill box. The diagnosis's aren't falsifiable and in multiple cases attempts to falsify a diagnosis proves the diagnosis.
There are also various absurdities with this status quo. The literal meaning of what a mental illness actually is in in flux and has literally changed multiple time over an older adults lifetime. If you meet 5 criteria you're healthy and get no assistance, if you meet 6 criteria you're definitely disabled. A bad reaction to an environment causing issues, the classic example being the child fidgeting after sitting in a desk for 8 hours being diagnosed with ADHD, leads to the child being blamed instead of the environment.
I don't think psychiatrists have no role in society I am just heavily sceptical that they're actually scientists, they seem like people using applied science like engineers.