Things like: It's normal to breast feed in public. Or the nation does not go bananas when a nipple is exposed on TV. Or how normal it is to sunbathe topless. Arguably this also relates to how normal it is for kids to walk around naked and families to be naked around each other.
If you're really interested, watch some older Dutch movies to see the normalness of naked, like Turkish Delight [0]. Or even have a closer look at the relation between the Professor and Raquel in the recent Casa the Papel. It's different from US series. More respectful, mature wrt women if you ask me. More emphasis on intelligence. Or on a beautiful woman in her 40s with normal wrinkles. The US, like on many other topics, seems to be polarized, caught between the hyper sexuality of Cardi B and the prude nature of American culture in general.
In particular, the pearl-clutching gender-specific moralising: it is absurd that an organ whose specific purpose is to feed infants by being inserted into their faces is censored specially from minors, whereas the non-functional copy of the organ in men which can’t even do that is apparently acceptable (modulo dress code, weather, etc, but you can walk around or swim or sunbathe topples as man, not as a woman).
Also the largest and best known breast cancer fundraising organization, Susan G Komen, has, in the words of wikipedia, "been mired by controversy over pinkwashing, allocation of research funding, and CEO pay."