Let me preface this by saying I am a man, and smoked a little too much, so I’m sitting here thinking… what is or was the original purpose of a bra? Weight support? Vanity? Covering the nips so people’s eyes met your eyes and you can have a normal conversation? Like what’s it all about?
They’re not. OP is asking the actual point of them, and you’re bringing modern politics into it, which are a very recent development. “Bras” go way back, like thousands of years BCE, all with very different functions.