They don't want the cause to be genetic because if it is social/environmental, they think that will be easier to fix. They are wrong.

From It's Fair To Describe Schizophrenia As Probably Mostly Genetic by Scott Alexander.  There is apparently an argument going on regarding the ethics of acknowledging the schizophrenia is primarily caused by genetics.  Alexander makes the extended argument that schizophrenia why it is reasonably clear that schizophrenia is caused by genes and why it is appropriate to describe it that way.

It is an interesting essay beyond my domain of knowledge.  His opinion and evidence appear sound to me.

Part of why it is interesting is that it is dealing with an issue, schizophrenia, which is in itself poorly defined.  Even though there is potentially a great deal of definitional argument, there is still much that can be known about the condition even when there is less than complete agreement and even when there is little settlement on definitions.  

And Alexander is a good catalyst.  There are certainly things about which he has great confidence, but compared to most essayist, he tends to be more open.  He genuinely wants to understand and is throwing open the floor for debate.  He makes his tentative proposition or speculation and invites additional evidence or better logic and reason.  His comments sections are almost always as important to read as his essay.  Something that cannot often be said for others.  

But as I am reading, I keep wondering, why is there this debate?  It seems clear that the crux is not about causation but whether it as appropriate to acknowledge the causation.  Which is quite significant because there are many such arguments and discussions.

Is it useful or appropriate to acknowledge a lab origin for Covid-19?

Is it useful or appropriate to acknowledge differences in mean and/or standard deviation of IQ between different groups?

Is it useful or appropriate to acknowledge the contribution of individual choices in life outcomes?

Is it useful or appropriate to acknowledge the contribution of individual behaviors in life outcomes?

Is it useful or appropriate to acknowledge the importance and role of culture in national outcomes?

Is it useful or appropriate to acknowledge the importance and role of institutions in national outcomes?

Is it useful or appropriate to acknowledge the importance and role of active policing in reducing crime?

Is it useful or appropriate to acknowledge the importance and role of genes and family structure in determining life outcomes? 

The list is near infinite of things which are either certainly true or probably true but which we are reluctant to acknowledge as true.

Why?  Why the reluctance to acknowledge that which either is certainly true or most likely true?

In the context of this essay, Alexander:

Why am I insisting on this so hard?

I think if E. Fuller Torrey had discovered that something fun and interesting like toxoplasma or social defeat explained 80% of the variance in schizophrenia, everyone would say “Oh! That causes schizophrenia!” and forget all the nitpicking. This would happen even though toxoplasma can cause other things, even though it might not explain the exact causal pathway by which toxoplasma causes schizophrenia, etc. I think people really want things not to be genetic, so when they do turn out to be genetic, they apply higher standards for whether you can call that “the cause”. Then people underestimate how much genes matter.

This is well-intentioned: people want to fight back against a disease, so they want to exhaust all hope of finding environmental causes (which they think they can change) before giving up and attributing it to genetic causes (which they think they can’t). But as we often discuss here, this is backwards - society is fixed and biology is mutable.