“Darcy isn’t actually socially awkward or uncomfortable, he’s just arrogant”
Darcy explicitly says that he’s uncomfortable around strangers and has trouble catching their tone of conversation or showing interest. He initially hovers near Elizabeth without talking to her to work himself up to speaking her personally. He admits that he avoids dancing in general, no matter where he is. Even when he’s trying as hard as he can to be pleasant and courteous, the Gardiners find him likable and gracious but noticeably stiff. Where Elizabeth shrugged off his admission of social discomfort at Rosings, during their engagement she actively tries to shield him from difficult social situations. He’s not the only who grows!
But Darcy is also arrogant—see his initial insult about Elizabeth, his high-handed interference with Jane and Bingley, his first proposal, his admission towards the end of the book. He’s snobbish and, additionally, deeply invested in believing his individual intelligence and morality are superior to most other people’s—a belief that isn’t baseless but which is exaggerated from reality (hence the unsubtle symbolism of the stream at Pemberley!) and which leads him to see those outside his circle of family/friends/dependents as inferiors whose thoughts and feelings he doesn’t really need to consider. This is a clear flaw that his character growth revolves around!
And … I mean, let’s be real, the idea that social discomfort and arrogance can’t coexist in one individual is an absolutely baffling take to get from fandom of all places.
