Hey, thanks for the insightful response!
I completely understand your take, after all, HSP is a personality trait rather than a diagnosis under the neurodivergent umbrella.
Typically, HSPs are more associated with having ADHD than having Autism, as usually the "joining of dots" is more accurate.
That said, there are plenty of cases in which Autism and ADHD exist as a comorbidity in individuals so it's entirely possible for an autisitic person to experience HSP.
And given that HSP is really just heightened sensory perception, it is correct that it can simply exist as a symptom of being autistic.
However, HSP can exist without either of the two diagnosis, too. Really, much more research on neurodivergence needs to be done so we can finally get the understanding it deserves!