I’m surprised that this thread is still going. Let’s have a look at some environmental biology:
Non-human mammalian neonates need the colostrum for immunity because they are typically born in the wild, where they’re not protected very well from all the parasites, etc. Similarly, they need to feed from their mothers because (even in zoos) there’s no effective substitute readily available off the supermarket shelves.
WHO recognises that many humans live in sub-optimal conditions, where there is no uncontaminated water supply. Therefore, bottle feeding is hazardous for many human neonates. Hence the boycott of certain pharma companies that have pushed milk powder in areas with poor water supplies.
The mantra that “breast is best”, in our Western world, with our good environment, our good pre-natal nutrition, our good (monitored) water supply, careful manufacturing of milk powder, doesn’t really apply to us in the same way it applies in other parts of the world. The “best” in our part of the world applies to what works the best for that fourth-trimester unit of the mother and baby. BF is cheap and it’s available on demand, which is great at 2 a.m. when you don’t have to do that complicated thing of making a bottle.
But BF is the worst kind of challenge when you’re post-birth and expected to perform; and the natural weight-loss of a newborn can only be within a certain (often not understood) percentage of birthweight; and there’s little recognition of tongue-tie and what that means; and there’s not much support for women trying to breastfeed with sore nipples.
The “best” isn’t much about our babies, after all. It certainly isn’t about what’s “best” for the mothers.