The wisdom of attempting to diagnose someone without a formal diagnosis is an entirely different issue, and I agree it is unwise.
The original claim was that saying that someone's anti-social behaviour was due to being neurological atypical, was an insult to everyone who is neurological atypical. This is clearly nonsense.
OK. Let's take an analogy. Do you believe that saying that a history of parental violence contributed to the boy to be violent in his own turn is an insult to everyone who was beaten up by their father?