The obsession with breast feeding is a religion, just like the religion of global warming.
Our now-4-year-old absolutely didn’t like breast feeding and we switched to bottles (though augmented with a breast pump) and he is bigger (not fatter), stronger, and healthier than all our friends’ and neighbors’ kids of around the same age. We are constantly amazed at how physically frail the children of the breast-feeding-worshipers are.
I’m not saying breast feeding is wrong. Again, we augmented formula with breast milk.
But it is a religion. Note the moron on this thread who claims formula is a “poison”.
And there are always exceptions - children with medical issues, Rh incompatibility, milk that doesn't come in or let down, etc. etc.
But as a general rule breast feeding is best. I imagine that your breast-feeding-fanatic friends have other issues as well (and I bet one of them is vegetarianism, which isn't good for young children). We were natural childbirth/breast fed babies, a little unusual for our generation (early 50s), and so are all our babies. We are all very sturdy and healthy as can be. A lot of that is genetics, of course -- we are descended from those tough Scotch-Irish farmers who settled the Shenandoah Valley and the Appalachians, with a good admixture of no-nonsense Irish.