[Groxx]

yeah, autism is very much an "umbrella term". we define it by the effects, not by any identifiable causes. there are still broad "less impacted" and "more impacted" cases, arguably a spectrum, but it's very very much not linear.

cystic fibrosis used to be under the (all-encompassing) umbrella "chronic fatigue" because, well, they were chronically fatigued. when its niche finally gained enough data to escape the umbrella, diagnosis and treatment greatly accelerated. of course, you'd expect that once a cause is identified, but umbrellas tend to contain many totally unrelated sub-causes with wildly different subtleties that just happen to fit a vague description that matches others.