It's lumping a bunch of things together because they are empirically linked together

People with sensory issues often also have more cognitive rigidity for example.

Autism, and many other psychological disorders, are quite literally just a lump of symptoms and presentations, because we do not have better options.

Sure, it makes navigating american health insurance easier if you can just say "Autism" and get various treatments paid for, but very similar diagnostic criteria and definitions are used in countries with fully socialized medicine.

Those people with those linked issues tend to benefit from similar treatment, and that's the entire point of a diagnostic criteria.

All the complaints come from people who seem to just not like the vibe of that?

Deal with it. Go fund more research into the heritability of neurodivergent pathologies if you want a blood test.

Some day we WILL be able to separate "Autism" into very specific diseases with specific causes, and some of those causes will have a genetic test. Unless we kill the concept of medical research because we elected morons who tear apart our institutions.

I have "Impaired vision", and I share that with people who are profoundly (but not totally) blind, and it does not matter that I can drive with glasses and they can't, and the name of that condition is not the important part.

All this handwringing about "but but but my mildly autistic son is mostly functional and I'm sad that he has the same name of condition as someone who cannot be educated past a 3rd grade level" is stupid. It does not benefit anyone struggling with autism to complain about it.

Are you aware that we have multiple medical conditions called "Palsy"s, and that they have drastically different causes and effects, such that my sister's Palsy which was caused by medical malpractice and prevented her from using her dominant hand in some cases is very different from my schoolmate's Palsy which left her wheelchair bound and requiring professional help day to day? They are both palsy because they are (partially) movement disorders stemming from nerve damage or dysfunction.

The horror!

I honestly can't help but feel like the main point of people whinging at autism being a broad diagnosis is because they don't like that it makes getting treatment easy (especially coming from "the economist").

Maybe I'm not being charitable. But that really does feel like the only real outcome of trying to piecemeal the diagnosis.

I don't believe research or treatment is negatively impacted in anyway by the diagnosis being broad. If anything, that opens doors so that research isn't accidentally too narrowly focused.