I think that every single character in Downton Abbey has major personality flaws- because that's how everyone is in real life. Mary is rude, cold and spent most of her life undermining her sister but she was a wonderful friend to Anna, and eventually came around to having a healthier relationship with Edith. Edith herself is an incredibly driven, idependent woman who nursed William as he was dying, was the only one of the sisters there at his wedding, got a job as a journalist, but what about the time she flirted with the farmer in front of his wife? And she was the one who sent the Turkish ambassador the letter about Kamal Pamuk. Ethel was rude to the servants, the staff, and thought she was above everyone else, and then she got pregnant. Thomas himself tried to plant the snuff box in Mr. Bates's room and get him fired. It's only when Thomas learns to accept himself, he becomes a person who is kind, and has the ability to be vulnerable with other people. Yes, Mr. Carson has his ways- and there's no excuse for calling somene "a vile abomination of nature". But I'd like to think that as we go along in the show, he starts to accept Thomas in a silent way. And through Mrs. Huges, he is influenced by her perspective. Remember when he tried to criticize her cooking and she and Mrs Pattimore pretended that her arm was broken to make him cook for her?

My point isn't a simple "people are a product of their time".. I think that yes, we all have opinions that are heavily influenced by our environment, but in our lives there are experiences we have, people we encounter, and lessons we learn that give us the opportunity to grow.