The truth isn't obvious. In the 1930s, 1940s, 1950s, it was 'obvious' to many people including doctors that bottle feeding with evaporated milk or formula milk was more scientific, more hygienic, and better all round.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2684040/

>By the 1940s and 1950s, physicians and consumers regarded the use of formula as a well known, popular, and safe substitute for breastmilk. Consequently, breastfeeding experienced a steady decline until the 1970s (Fomon, 2001)