Smegging body hair debates! Chest hair edition this time, instead of pubes. Okay, some people prefer more hair, some less. Some people grow more, some less. And the fashion has changed from time to time (although, as usual, if you're a hirsute woman you're pretty well screwed no matter what time period we're talking about). But once again we're getting the "ew! hairless = prepubescent" in the comments. Can we please just all agree that no matter what gender human we're talking about, an adult body does not look like a prepubescent body whether it has hair or not? What a way to insult men who just don't grow much in the way of chest hair. (There is so much grottiness to unpack here. The underlying pattern is a continuum from hairless child to hairy grown up manly man, which implies that men with less hair are like women and women are more like children, and urgh! Stop! Yes, it's patriarchal, and if you don't believe that women are policed to be in the "hairier than a baby but not as hairy as a man" spot on the spectrum, be a hirsute woman and let your facial hair grow a bit.)
Not to mention, it's such an arbitrary sentiment. Lots of babies are born bald . . . we don't see a guy with a shaven head and go, "ew! he looks like a baby!" And strangely enough, although I didn't have much leg hair or armpit hair before puberty, nobody's saying I'm trying to look like a little girl if I shave my legs or pits.
So. That's my rant about checking your assumptions on cultural exaggerations of sexual dimorphism for the day. Adult bodies are adult bodies whether they've got hair or not.