Many autistic people prefer to say they are autistic. Hopefully it's become clear that I think this way, and I can't just not think this way. Thinking is my main way of interacting with the world, it's not just "a trait".
You can ignore the parent comment. It's become fashionable these days to not use certain descriptive labels in a traditional manner because a certain class of people feel it's dehumanizing by "reducing one to one's condition". For instance, someone isn't "diabetic" they're a "person with diabetes", because the diabetes is just something they have it's not who they are. You're not "autistic", you're a "person with autism", and so on.
It's just a semantic game that is only making communication more verbose for no meaningful gain, as if everyone didn't already understand "autistic" to mean "person with autism".