I think the autism comment is more of an insult than a statement.
I have actually noticed that I have a fetish for airplanes considering I watch them often on YouTube departing, arriving, blasting off (agaaain! *twinkle #pokemon reference), et cetera. My Little Pony is not as prominent, but it's still something I desire unusually.
I guess you can say I might have some form of autism, but I do have a relative who actually does have autism, and I am not so similar to him considering I'm a lot more social and vary my interests, so it's safer to say I don't have autism. Again, I might be a normal aviation geek (who can't fly dammit!) whose hobby is... aviation!
Basically... we all have our hobbies. Other people will insult you with a comment (ie, you have autism) so they can feel better about themselves.