Yeah, I think you are picking nits here a bit. In your own language, use what you are comfortable with, but trying to change another person's language, when that language isn't necessarily in any way widely offensive, is probably a bit much.

The bipolar community has the constant debate between "I'm bipolar" and "I have bipolar disorder." My take: I use what I am comfortable with knowing other people prefer a different reference for themselves.

I was having a similar conversation with my mtf transgender daughter last night. The language and lingo and slang around the LGBTQ community is constantly changing and evolving, and her take on it is that she knows what she uses in reference to herself; she doesn't have the time or inclination to be offended by someone else's preference in language if it is simply a matter of preference over offense. She can't keep up with it herself to be quite honest; she doesn't expect everyone to necessarily use exactly the same language. As long as the intent is not offensive, to each their own.

Be comfortable with how you personally reference autism, and be understanding that variations of terminology and phrasing are also acceptable to other people in your exact same situation -- you don't get to decide for them.