There’s nothing wrong with building a MOC to appear proportionately feminine. At the end of the day, we’re discussing appearances here, and a key part of the character can be building with a similarity/callback to real life. Canon can go to heck.
The issue is sexualization, the objectification of the character/gender. I’m not sure whether people are unaware of the issue or just don’t care, but you don’t exactly see tons of Tahu MOCs with defined codpieces, right?