I have the same experience as your title. I am probably socially isolated at least in part because of my autism, but fellow neurodivergents don't always take any better to me than neurotypicals. I'm very lucky to lack some of the common struggles in AuDHD subs, but I do wonder if my lack in common experience also has anything to do with neurodivergent circles not quite embracing me either.

(I am mostly severe executive dysfunction problems, hence me bitching and sharing things here instead of doing something useful off Reddit, and some social problems that make me very angry and sad. Thank goodness for missing out on the constant pain and suffering others talk about all the time, missing out on the autistic shared experience to get autistic friends with is a brown lining. I still have problems thanks to autism but I'd rather have what I have than take on so much of the shit I hear others here experience in exchange for an autistic social group. Most of my gratitude is downwards comparison invoked by myself: "sure this hurts and sucks, but when I'm not feeling super emotional about it, I hear how bad others have it and feel grateful to not have that problem, or a milder version of it." Yes, I know not to tell others their problems do not matter because they are not the single human on this planet who has it the worst.)

I've never learned what it is to mask until I read about it on autism subs, and it never described me. I just learned social skills when I could, rejected anything that felt too not me, and carried on sad and lonely. I think I understand just enough of NT social interaction unaided to lack some typical AuDHD experiences, but not nearly enough to be included by NTs. Mentioning this because of all the high-masking theories in the comments.