Twitter is basically a gold mine of retardation, and you can literally collect endless cases of just how insane, wrong, and retarded they are about everything. There are more examples I could give, but I want to list some of the most obvious ones, because as far as I know nobody else has done. Also, because it'll help counter-act their insane view of themselves as occupying prime digital real estate or whatever.
They have a major habit of writing dismissive / smug / cynical sounding posts, where they basically attempt to make some normal behavior come across as beneath them, inferior, irrational etc... only for you to realize that the writer has no clue WTF is going on. Sometimes they get the behavior they're describing precisely backwards. It's like reading a Martian attempting to pierce together human social norms.
They'll come up with convoluted explanations for things that have very simple causes, while thinking that the more complexity they add, the more accurate the final conclusion becomes -- just the opposite, lol. It becomes worthless.
They'll write completely fabricated / totally wrong BS / fan fic in a tone of such smug superiority that it makes it sound as if God Himself had told them personally. Or as if their view were so true that it didn't even require evidence or reasoning to justify (often the mistakes are high school level). This seems to be the result of grade-inflated college degrees.
They'll attribute some grand long-term cause (like Evolution, Darwin, Female Nature, etc) to things that only started ten or maybe fifteen years ago at the latest. Sometimes they'll even go further and claim that some behavior that is obviously not fitness-enhancing or is maybe even totally destructive is UM AKSHUALLY fitness-enhancing, complete with some retarded made-up vignette of hunter-gatherer life.
They'll problematize and pathologize all kinds of things that are totally normal and natural and helpful, while turning a blind eye or even being in favor of things that are wicked and obviously sick. Sometimes they seem to be judging healthy behavior by the standards of sickness / mental-illness.
In many cases the discrepancy between their own self-descriptions and the reality is so severe and jarring that you can only really understand what they're saying by flipping the meaning of the words around -- it's like they're so wrong that they almost get it right (almost). Then anyone who points this out has to deal with the inevitable temper tantrum (from some thin-skinned dork who can't handle reality, lol).
They all seem to think that they belong to a highly exclusive club which the rest of us jealous inferiors are too low status, unintelligent, poor, and so on, to join -- they don't realize the whole world is laughing at them, and nobody takes their lame fan-fic seriously.