The pacifier and bottle are artificial imitations of the breast, so just because a recommendation applies to them, doesn't mean it applies to the "original". Pacifiers and bottles are detached items, and an older child is more likely to carry them around all day, which is bad for jaw development and bad for the teeth. However, with breastfeeding, an older child most likely only nurses a couple times a day, for a fixed period of time (a nursing 2yo still wants to explore, do other things).
If you think about it biologically, when you cease breastfeeding at a young age, you must replace that milk with something ie cows milk. It makes no sense that cows milk is more healthy for a child than human milk. It's more convenient, but it's never more healthy. A child who nurses untill age 3 or 4 may never need to be weaned to cows milk at all. My daughter had trouble digesting cows milk, and it's actually one of the most common foods children are allergic to. She nursed until she no longer needed "milk" as a staple in her diet. When she weaned at age four, she no longer required "milk" for her protein and calcium and other nutrients milk provides. Most nursing tollders and older children are eating all the things a cows milk-drinking child would. Cows milk just replaces the human milk - everything else is the same. People seem to think that older nurslings aren't eating other foods. i'm sure that's just because it's so misunderstood. My daughter's diet is excellent.
I suppose it would be hard for someone who never nursed an older child to understand that it's not about the mother at all. The mother is usually more than ready to let it go; I was OK with my daughter weaning from the time she was 16mo, but she wasn't ready. Nursing is very important to alot of children and just because most kids are forced to wean earlier, their need isn't diminished. It's not about keeping them a baby, or about the parent taking control; there's precious little that a 3yo has control over in his life, and it's actually beneficial to give him control over a safe, but meaningful decision. If you think about it, nursing is something they want to hand on to, but they want to also move on to other things; so making the decision, and they WILL make that decision, a decision to let go of something that they love, is a very important developmental step. It encourages independance, thought process and growing up, contrary to popular belief by those who have not witnessed/experienced it.
I was encouraged by my daughter's doctor, pediatrician and a nutritionist to continue nursing past age one, as she was small for her age (turns out, perfect for her), and human milk is better for her than cows milk. She gradually dropped some nursing sessions (for cows milk, which it turned out she had problems with) until she was nursing twice a day, then once a day, then once every few days and then one day, at age four and a half, she told me that she was finished nursing. She was proud of her decision, and when she thinks back on breastfeeding it's a happy memory; more of a feeling than actually remembering nursing. She also seems to be developing a healthy view of the human female body; unlike me, who was extremely shy and prudish. She has no clue, even at age eight, that breasts are sexual. Why would she? She hasn't been taught to be ashamed. She does know that it's socially appropriate for girls to wear tops, and she does, but she's not ashamed of her body.
Nursing to age four for us has shown to only have had benefits.
I sometimes still rosk my eight year old to sleep, she she's sick or upset, and I sit with my 10 yo son (who was forced to wean at age one) when he's upset until he falls asleep. just because they are growing up, doesn't mean that i still can't be the mommy.