Something being a table is a label we slap on it to abstract certain attributes, that allows us to reason about it without having to think about all of the non-table-attributes it has. What do tables do? What can we do with them? We can put things on, eat off them. We can’t feed them to our pets. We can’t use them as a trampoline. The object being “a table” is just a categorization we make to allow us to think about the object; it isn’t something that the object is.
Similarly, people aren’t “autistic”. They’re just people, who have certain traits, which psychiatrists have decided should be lumped into a category called “autism”, because they’ve noticed a cluster of other people who have similar traits. So, from this standpoint, someone “being autistic” does not tell us anything. We can already see that person’s traits or characteristics. That categorization might be helpful to some people, and it might be harmful to other people; and they should use or avoid using it accordingly. But they can choose to do that, because “autism” isn’t a “thing” - it’s a mental construct.
Eczema is a skin condition which happens to some people, it’s not something that happens in most people. But we can see evidence of varying degrees of severity of skin damage due to eczema. This condition can happen for any number of reasons, immunological, endocrinological, or some combination of factors. There are different types of eczema, but for ease for conversation with anyone other than a doctor, you just say you have eczema.
Same for mental conditions, they have their underlying causes, and some representative characteristics we found on average and grouped them as classes for ease of diagnosis and treatment.
I understand the folly of mischaracterizing, so it doesn’t make sense for researchers or medical professionals to not care about the categorical distinctions.
However, as far as the normal public is concerned, someone’s problem is their problem, and they don’t owe you a detailed explanation of their condition, or a doctors note because you’ve been socially offended (I understand maybe that’s not the point in either of your posts, but I thought I should say it now that it occurred to me in the flow of this post).
My argument isn't that psychiatric symptoms don't exist or aren't real and there is no real underlying phenomenon. My argument is simply that we've drawn the lines between the units of study too high up and we should be more granular. This level of nosology was chosen in 1952. Do you really think they got it 100% right almost 75 years ago? And what is the mechanism for defining and maintaining these categories? A bunch of committees get together every few years and decide on them, then they tell us all what's "true". Bullshit. What are the odds that a committee will define itself out of existence? Pretty slim. [1]
I have traits that could be considered as autism, ADHD, obsessive compulsive personality disorder, PTSD, bipolar II, social anxiety disorder, and probably a dozen more disorders. But by quantizing the disorder at the current level, by necessity, the other traits are cropped out of view. Relevant information is lost and irrelevant information is blurred together. And the level of overlap between disorders is absurd. They cannot possibly be "real" because the lines between them aren't even distinct.
The useful unit to study is the individual trait, not the cluster of traits that is different in each individual. The traits are more granular and map more closely map to underlying biology anyway. The current model is akin to what the geocentric model was in astronomy. It's outdated, wrong, and holding us back from a more accurate, detailed view.