I think this is a useful read
Does Mental Illness Exist?I don't think I necessarily disagree with this strong sense that the individualized management of people's problems is without value, and I'm wary of an outright rejection of the healthcare system in spite of it's clear inadequacies.
My understanding isn't the denial of there being a biological basis to our mental issues, but that there is no clear demarcation of a mental illness based on a biological etymology in the way that other physical diseases are identifiable. To which then mental illness isn't then defined by biology, by symptology based on how functional someone is socially, like their relationships are fine, they're not fucking up their own lives and they're able to work. If none of these a problem, someone might be possible to diagnose as say autistic but because they have social supports and reasonable degree of cognitive functioning, that they don't need much support from a healthcare system. I've had a lecturer posit just that, that an example of some kid with autism in a small town community that looked out for 'em didn't have a disorder. They seemed to take a pragmatist approach in which the label/diagnosis was a useful one for accessing supports when they're needed and useless when they aren't.
But in a strictly social model, a person's functioning may not be a sign of problems with them but of society and it's current state. As such, the idea of mental illness becomes defined by how acceptable some behaviour is. Which I think as a point has some merit but shouldn't be taken so far as to delegitimize the utility of services for people who do need it. Especially based on the rapaciousness of pharmaceutical companies in the US or the lack of radical effort to overcome capitalism which destroys social relations and people, and doesn't offer direct social solutions but only inadequate individualized management.
As far as I can tell, demarcating what a mental illness is, faces the same issues of demarcating a science as expressed by Paul Feyerabend. That there is no clarity on the issue, but there are clearly people that have difficulties that need support and whether someone calls it a mental illness or wants mental illness to be viewed differently then that's fine. But mental illness will necessarily exist within our current social relations just as the divine right of kings was real in it's own time, it has a necessary function.
I suppose the thought experiment to pose whether mental illness exists would be, to what extent does one thing our current conception of mental illness and the difficulties presented by those deemed mentally ill would fade away in society changed in a certain way.
Because looking at the wheelchair example...
it's easy enough to see how society can be made more inclusive. But it's not apparent to me how some folks with schizophrenia are so easily accommodated. I suppose there might be the suggestion of how such tendencies aren't stigmatized as mental illness in the overly rationalistic west but are characteristics supported in mystic fashion. And so the conception of it being a disorder to be treated becomes obsolete. But that exists within a particular kind of society that has a place to which those characteristics are rewarded or sought.
What kind of society post-capitalism or something would make many 'disorder's obsolete' as problematic.
Our knee jerk reaction is that they need help, but why they need help is based on a functionalist sense of them being maladpative and problematic for our current social standards. But I don't think such judgements are made irrelevant, as long as society stands as it is, so does the problematic nature of some things. Positing that things are deemed socially problematic doesn't make schizophrenia any less difficult.
I'm thinking even in an ideal world, there would be difficulties that arise that seek support which may not be so medical but more directly social. And so in a sense things would no longer exist as they were, but would be conceptualized in a different form relevant to social conditions.
https://www.ethicalpolitics.org/ablunden/pdfs/For%20Ethical%20Politics.pdf#page90
-For Ethical Politics