Evidence of correlation in genetic studies doesn't answer the questions you were asking. The claim you made was that you don't believe psychological disorders have different causes.

Humans share 98.8% of genetics with chimpanzees. That doesn't tell you humans and chimpanzees are the same. It tells you where to look for the differences between humans and chimpanzees. A similar study to the GWAS study you cite shows that arthritis and type 1 diabetes have significant genetic overlap (https://pmc.ncbi.nlm.nih.gov/articles/PMC10291128/). That makes sense they're both autoimmune disorders where inflamation plays a major role. But arthritis and type 1 diabetes are not the same disorder.

The GWAS studies narrow down the search for genetic markers. They don't establish some sort of continuum for disorders all controlled by a single cause. They don't mean the difference between mental disorders is environmental. They don't mean that medicine or psychological disorders are social constructs or that there is "no reality to them".

The question of whether two things are distinct is determined by any one difference. 1 and 2 are distinct despite differing by only 1. You can list thousands of ways they are similar (both integers, both positive, both less than 500, both written with marks on a page). But those similarities do not make them identical.

That's why I'm saying once again that if you want to focus the conversation we need to talk about the genetic differences, fMRI differences etc between disorders and then you would need to make the case that those differences have the same cause. At any rate, I don't feel like pursuing this any further, but I wish you well.

P.S. I noticed in one of your earlier comments you said something about psychotherapy. Just in case it's not clear, psychotherapy is very different from psychoanalysis, which is what Freud was doing. Freud has a bad reputation as someone whose theories haven't held up well and who engaged in deliberate fraud. Psychotherapy is an evidence-based branch of medicine and is rightfully well regarded. You'll find that I've several times on this site and elsewhere recommended everyone use psychotherapy just like everyone should have a dentist. I just wanted to clarify that in case you were under the impression that my statements about Freud applied to psychotherapy. However, psychotherapy doesn't have anything to do with "attempting to remove internalized violence against self/other."

I get the feeling we're completely talking past each other. I never claimed that psychological disorders cannot have different causes. They may mostly be variants of a living organism's spectrum of maladaptive reactions to various adverse circumstances, yes.

You seem to read what I write, then make assumptions what I might be saying, and then reply to your assumptions, and ignore most of what I write (e.g. about your claims of "heritability"), which makes this a very weird interaction overall.

I agree with your idea of just letting this be, as I don't find it a very productive exchange.

I don't know why you keep coming back to fMRI and genetic markers, because, again, nothing of what I was trying to say has anything to do with whether there are measurable differences on that level or not. You seem to think that "symptoms" are described in the disorder definitions, and anything you measure is the "cause". Again: To me, it is similarly possible that both are symptoms. You can use that for diagnosis if you feel like you need to make this discrimination, but that doesn't say anything about treatment or etiology.

> psychotherapy doesn't have anything to do with "attempting to remove internalized violence against self/other."

I take it you do not consider the EMDR protocol, ACT, CBT, IFS, ego state, Schema, CFT, EFT, SE, DBT, MBSR, DBT, IPT, systemic therapy, gestalt, to be "psychotherapy" then. All of them work with and address internalized violence against self ("inner critic", self-worth, other negative thinking patterns; chronic often suppressed feelings of shame, anger, grief).