I've heard this before, and I think it rings incredibly true. The basic idea is that every group of people, office coworkers, a particular group of friends, a classroom or family will at some point develop their own mini-social rules, norms, and customs. What topics are okay vs taboo, when and how to interrupt others, what type of humor is on or off the table, what or what does not count as tmi or overstepping boundaries, for example, will all be determined on the fly when any new social group comes together. In other words, every social group is its own mini-subculture.
Most "NTs" seem to be able to read the subculture of whatever group they find themselves in relatively quickly and get along with it. ASD does not. This is why we may even struggle when hanging out with other "geeks" or "nerds". "Geek" and "nerd" subcultures and friends groups frequently develop social norms like any other group. If you're not good with that, you're out of luck.
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AQ: 36 (last I checked :p)