It’s not the word they use, it’s the connotations they feel their words carry. I prefer the term ‘autist’ as a noun rather than using the descriptor. An autist practices autism as an artist practices art. Not everyone who is autistic practices autism, as not everyone who practices art is an artist.
Therefore, I am a lousy autist. But, like the artist, I believe my autism is both a blessing and a curse, as any starving artist will say of their art. There are both artists and autists who have the potential, but never make an art form of it. I’m a lousy autist, but I try every day to be the best expression of myself, which certainly includes autism.