Not all of it.
There is some basis for fact in some of it.
Breast feeding is protective against food allergies to a degree.
Living in a too clean environment keeps the immune system from learning how to fight disease properly. Early exposure to dirt and germs trains the immune system to NOT go into a hypersensitivity reaction over harmless substances.
“Breast feeding is protective against food allergies to a degree.”
That’s about the only one.
Provide references to any of the other.
And even that is sketchy. Breast feeding among the population claiming food allergies today I think is higher than in the past.
In fact, now that were talking about it, perhaps the extra nutrients and consistency of delivery from bottle feeding and formula contributed to stronger immune systems developed early and functioning over a lifetime.