I suppose I see abnormal meaning the same thing as atypical...its not as 'common' I mean obviously there are more neurotypicals than people with autism..so makes it not typical not sure why abnormal would have such a different meaning to that. Or has the word abnormal just developed a negative connotation?

Of course neurodiversity is important and differences can be positive, however it also should not be ignored that things like autism also come with quite a lot of difficulties and can be disabling in some ways. Though I am quite certain this society makes it more disabling than it might otherwise be.