I do not think it is failing to dance that is Darcy’s downfall however but his refusal to socialize at all and his obvious distain for the local people.. I can identify with Darcy based on my experience at his same age of being expected to be sociable as the newly introduced manager of a group of employees. I did not have Darcy's wealth or "high birth" but as their new leader, the people there did expect me to socialize and mistook my over-correct manners for lack of ease and friendliness.
People in any social class are certainly capable of rudeness, but I think quieter, more subdued personalities are often misunderstood in public situations.