I worked (admittedly as a custodian, so not an expert at all) in close contact with people who had antipersonality disorder. These were people who had been convicted of sexual assault and had served a sentence then had been deemed unfit to return to society. I don’t believe any of them could get any amount of treatment that would have made them truly safe around others, even if they behaved well on their wards.

Mental illness can almost never truly be cured, and some people can be simply too dangerous to be allowed complete freedom. It’s sad to think about, but I think until we have a better understanding of the mind and how to better treat people with issues like this, it’s better that certain people stay “locked up” as it were. So long as they are given humane treatment and accommodations, of course.

Psychologist here, depends on what you mean by treated. Most mental illnesses aren’t like a cold where you’re able to take some medication and get rid of it, they’re more like a chronic back injury that you learn to manage. For most people, some combination of therapy and chemical treatment is sufficient to allow them to live a life where their mental health is managed. There are people whom chemical treatment doesn’t work on, sometimes because of unhealthy brain chemistry, and who are unwilling or unable to participate in therapy. Unfortunately for these people, there’s not much that can be done for them short of a miracle.

Schizophrenia can be untreatable.

Fachism sometimes too. \j