I have been in social isolation for 6 years, only interacting with my parents, who fight constantly.

I am sure I say stupid or awkward stuff when I try to express my opinion or try to be funny. I never get shamed or mocked.

Maybe I get mocked when I am not there, I don't know. Maybe I can appear to be normal. But I do hear others talk about some people with bad social skills or awkward or odd behavior. (Lotś of people like that in hard science/academics)

How come people around you shame you? Are you misinterpreting? Or are you hanging out with the worst of the worst people?

And actually, if people don't say a thing, you can't learn, because you do not know you are being awkward, mean, odd, strange, whatever. When they shame you, you can learn. So while I understand why it would frustrated, what you say doesn't counter what I suggested. The people that are most blunt are actually good to learn from, in a way. Sure, people that give feedback and try to be inclusive towards you are way better.