It was me who was the thumb sucker and no, neither I nor my brother have an overbite. Neither do any of my children, who have all been ebfed. As I said, all my kids have perfect teeth, as well as beautiful, straight, even teeth, but then, they never had a dummy/sucked their thumbs or whatever.
Even if I did have one, it's hardly physical damage, really is it? Many people have sticky out teeth and suffer no ill effects whatsoever.
Re: the comfort thing, most women who BF older children do it on a don't offer/don't refuse system whereby the children are not given the breast at the drop of a hat, only if they ask for it. EBF does not hinder a child's emotional development. There are many ways to comfort a child, the breast is just one of them. I think that there are many misconceptions surrounding ebf and how a child matures. Children who are bfed longer than average are just normal kids with normal lives who do all the things that other little children do. My eldest son is now 20, in 2nd year at one of the countries top unis, doing one of their most challenging courses. He lives away from home and manages his own life. DS2 is 17 and will be starting college after the summer, in spite of having AS, My other three are aged between 13 and 7 and are all normal, well adjusted children who have friends, hobbies etc. They ahve not been harmed or held back in any way, in fact ebf halped to give them the confidence that they have because they were allowed to move at their own rate.
As for never having heard of anyone nursing past 2, that may be because we tend to keep very quiet about it because of the negative attitudes and judgmentalism that surrounds breastfeeding past babyhood.