These guys are missing the big picture. Jon rose to where he did without knowing who he was. If they don't think that missing out on a mother's love damages a child (she wished him dead, to his face in the books) then they are the ones who know nothing. Sitting at the back of the hall during feasts, being told he'll never inherit a thing, in a class driven society and being constantly reminded he is a product of shame, could have made him cold and brutal. It didn't.
He was a loner, with a chip on his shoulder for sure, but he chose to do everything he could for the good of his people, time and again. If anything, he's proven the Stark blood and Ned's teachings always meant more than his secret blood. He made the choices on his own, unlike Rhaegar, who let some prophesy guide his decisions. He may die saving humanity, but it won't be because he was a Targ. Whew! Glad I got that off my chest!