...not to say he shouldn't have known the effect he had on others - his attitude, and that he should have cared more about it.

But I'm thinking about the possibility that certain people who find themselves wanting to maintain high standards for themselves mistakenly not only become hard on themselves but also become hard on others or even on the culture at large. Darcy is described as "fastidious" (aka hard to please). Also, the less general society knows of someone's character (such as being new to a neighborhood) but is acquainted just the outward appearance and circumstances (money, etc), the less favorable a person like this appears to others, unless/until that person is seen in action doing something he/she values and prioritizes highly (such as his/her occupation or philanthropy, etc).

I'm reminded of once when I was new to a job, that there was a person who I was going to work with who was so into her work and frustrations with it, she was very curt and impatient with me who was brand new. And I was none too happy with her and her attitude towards me. But her attitude wasn't caused by me - it was an overall unhappiness with the "system" we were working in and she was venting. It wasn't until later on I learned how competent she was. But it didn't help working with her, since she really wasn't aware (and didn't care that much) about how she worked with others, since she didn't deem that very necessary to her job. That wasn't her competence. I know I've fallen into such situations inadvertently as well, and it wasn't until some social fallout that I realized how I appeared to others.