Modern formulas are almost the same as breastmilk.
Not true !
The same claim was made in 1900 and before. Modern formulas are only superficially similar to breastmilk. Every correction of a deficiency in formulas is advertised as an advance. Fundamentally, formulas are inexact copies based on outdated and incomplete knowledge of what breast milk is. Formulas contain no antibodies, no living cells, no enzymes, no hormones. They contain much more aluminum, manganese, cadmium, lead and iron than breastmilk. They contain significantly more protein than breastmilk. The proteins and fats are fundamentally different from those in breastmilk. Formulas do not vary from the beginning of the feed to the end of the feed, or from day 1 to day 7 to day 30, or from woman to woman, or from baby to baby. Your breastmilk is made as required to suit your baby. Formulas are made to suit every baby, and thus no baby. Formulas succeed only at making babies grow well, usually, but there is more to breastfeeding than nutrients.