If there is money to be made the medical establishment will put much more effort into that area than if there is not
Bringing it back to the DSM: The more human states of mind that can be classified as a "psychiatric illness" the more money there is to be made in marketing various therapies
This is glaringly obvious in drug development but it applies to all forms of therapy that can be done in a way with a gate keeper who can charge a toll
Like, we can't sell treatment's for people's sixth thumbs because virtually no people have a sixth thumb and it's unambiguous that they don't-- and even among any who do it'll probably be clear if it needs treating or not. But I can sell a treatment for your hyper-meta-ego because who is to say if a person has one of those or not or if my treatment of it is successful or not?
Wouldn't we expect it to be more true the fewer objective measures there are? Like if a treatment is supposed to improve blood sugar, and we can measure blood sugar cheaply in real time... we should expect misaligned incentives to have diminished effect compared to something where there is less ability to objectively measure, such as pretty much anything in psychiatry.