Depends on the context. It can be used as an insult, but can mainly be seen when looked into as a neurological difference in a person that means they can process information faster. This is usually viewed as a good thing, however due to the complexity of autism, no one actually knows enough about it to comment on it, hence, it is used as an insult.

Sort of it’s a disorder so it’s not really an insult because if someone has autism and you tell them they have autism it’s fact not insult

kind off I think it is

yes it is