Why would it be?

I have Autism and i dont think so, but i feel like some people who have these might talk about sex/masturbation more then neurotypical people that's what i think

My cousin has ADHD and if anything the medication has slowed his development and probably reduced his sex drive. Maybe untreated ADHD would cause more horniness

there are plenty of psycho-sexual disorders...but they have nothing to do with autism.

Yes, ADHD and anxiety.
No, no reason it would make me hornier.

Just based on the people who have identified as having these conditions and other things they have said, I get the impression there is actually a slight delay to making the mental adaptation from the sex-free world of pre-pubescence to being fully in touch with ones new, sexual nature.