Mental distress/disorder cannot be treated properly because of the strong for-profit motive (unrestricted greed) that these privately-owned (sometimes publicly traded) mental hospitals and pharmaceutical companies have.
Mental hospitals are effectively a prison. Locked doors, removal of rights once committed, coercive and sometimes forced treatment and restraints, being told that you have a lifelong disease (with no measurable physical damage -- fMRI scans are not indicative of damage) that needs drugs for the rest of your life, and getting billed an exorbitant amount - to name a few things that are wrong.
If your rights are violated and you are declared incompetent (which is pretty common if you are unstable or in crisis), it's an uphill battle in special courts called Mental Health Courts. It's difficult to get a second opinion from a third-party psychiatrist, or to contest treatment orders (such as mandatory intramuscular antipsychotic injections or ECT which respectively have a very potent and long-term effects).
The conversation needs to be shifted towards the Soteria House paradigm.
This article sums this model of care pretty well: https://www.madinamerica.com/2019/09/soteria-house-heal/
They have very impressive results, particularly in regards to schizophrenic and psychotic patients, and do not use life-long tranquilizer prescriptions to achieve their results. It needs more study, it needs more implementation, but the core of the model is that it builds a supportive community around vulnerable people -- instead of caging and viciously profiting off of these people.
I spoke on this matter in the past, and you can read my thoughts here: https://news.ycombinator.com/item?id=34029719