It seems like it goes more or less fine in practice, and I reckon this is probably because these communities end up being self-selecting to some extent. That the type of autistic person who thinks this sounds like a great idea would also be the type who'd have an easier time in this type of community, while the type who thinks this sounds like a terrible idea wouldn't move to that type of community to begin with. And that even of the former group, that different intentional communities would end up dominated by different types of autistic people who tend to get along better. You wouldn't just move in without any idea of who your neighbors are.
Speaking for myself, I've attended a monthly local autistic adults group in person, I've lived with my autistic brother for most of my life, in my time in public school I had special classes with other ND students and had a few ND friends, and I even spent a year at a dorm school that teaches independent living for ND folks. So for me the idea of living with other autistic people of a diverse variety seems pretty doable. There would obviously still be a number of problems that I'd need to solve with regard to interpersonal interactions or hypersensitivities, but that would still be the case if I lived in a predominantly NT community anyways.
You shouldn't doubt yourself.