I watch the show a lot, I really enjoy it. Sheldon definitely seems aspie, to varying degrees in different episodes. Obviously, for TV entertainment his quirks are more exaggerated as comic than a lot of normal aspie traits.
It might technically be offensive to aspies, but I find it funny normally. Episodes where his mother are involved seem to be a bit past the line though, they seem to portray him as a crazy person or something.
His social skills are evidently not great, he asks whether or not things are said sarcastically, and offends people without meaning to. (realistic enough)
However, he is also very arrogant because of ahigh IQ, which I find seems to be connected to his traits in the show, although that is massive stereotyping of aspie personalities because I, for one am not particularly of a massive IQ or feel superior to people around me.
I could carry on all day, picking out every little thing about him which is or isn't offensive or accurate, but at the end of the day he is the character most people keep watching for, so even if he is a little offensive, he is still pretty funny.
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Female, 16
Knowledge is knowing that tomatoes are fruits. It takes wisdom to know not to put them in a fruit salad.