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?
I don’t have any sources or anything, but I’ve seen this anecdotally mentioned a lot by trans women. I do know that estrogen thins out your skin and I wonder if it’s related to that. Though, with all the stuff estrogen does, sensitivity might just be related to estrogen itself and not the byproduct of some other change.