Earlier quoted context omitted.
The diagnosis criteria for most mental illnesses include that the patient is negatively affected by their specific symptoms. Or regarding the specific quote, in the context of going to a normal school, "severely gifted" might be the right word for describing these children. If these children are given something meaningful to do in school instead, then the moniker would not be apt.
> The diagnosis criteria for most mental illnesses include that the patient is negatively affected by their specific symptoms. Even if this were true (which it isn't) the psychiatrist can always argue that the fact that someone else doesn't like the symptoms negatively affects the patient and therefore he is ill. Circular reasoning like this is common practice.
Maybe I was being too general, but the diagnosis criteria I remember from when I've looked at such (including ADHD, Autism spectra disorders, and Depression) have included such qualifiers, IIRC.
Checking ASD, the following is one of the criteria:
The deficits result in functional limitations in effective communication,
social participation, social relationships, academic achievement,
or occupational performance, individually or in combination.
Of course the diagnosing psychiatrist could always fudge the facts, but arguing whether or not psychiatrists accurately apply diagnosis criteria is a different matter to arguing that "to avoid one or another mental illness diagnosis, [...] you can't be extraordinary in any way".