Medieval armor was usually made for just men, female soldiers were unheard of, and the armor for the men accentuated their masculine parts in the chest, and so if they made armor for women, it would as well, maybe not to the extremes they go to in skyrim, but they would accentuate their femininity at least a little.
There were some women fighters, there is no evidence of boob plate in any of their gear or in period depictions. Armor doesn't accentuate anything. It's meant to protect the limbs and vital organs. The armor you're talking about for men was dress armor.
Which is why only the armors that can afford to sacrifice practicality for aesthetic have the "boob cups" : Steel Plate is reinforced and padded enough to avoid the drawbacks of working Boob Plate in, while Ebony is outright indestructible. A weakened piece of an indestructible material is still unbreakable. The only real threat they face is the aforementioned sternum-smashing... but that's easy enough to solve simply by using a rigid material contoured so that it keeps a good half inch or so away from the sternum, with significantly less space along the sides, belly, briasts, and top of the armor instead of the sternum.
Half inch? I'm sorry, a half inch of padding is not going to make any difference when what we're talking about is a sharp seam pressed up against a bone. You've heard from armorers and armor experts in this thread what this means and yet you're doubling down on your defense of ebony and steel plate as practical armor. It's almost humorous at this point.
The long and the short of it is that it is all about eye candy: for which I am a personal fan, as seen here in my http://i1224.photobucket.com/albums/ee378/jhallard/sample.jpg in Skyrim and in http://i1224.photobucket.com/albums/ee378/jhallard/Solona1.jpg. Skyrim is a fantasy RPG. It's about stepping out of the reality of our current lives; good, bad, or indifferent. Letting go of the stress that otherwise unfortunately makes up our lives the Twenty-first Century.
If you want your characters to look like strippers, that's fine for you. Others have different aesthetic preferences.