I think they are just an expression. To my understanding, the only shift there was, based on your testimony, was your intention, and because you associate dressing in a certain garment, clothes, and makeup with that ritual/practice, you enhance your intention because you are projecting your energy into those items. I believe this is also why special clothes and garments are used in rituals: whether conscious or not, you grant them sacred value when you put them on, so you are already manifesting even before you wear them.
So, in short, I think clothes and items only help amplify the energy because you project your manifestation willpower into them; it has nothing to do with the "labeled" gender society created around those clothes. I mean, I personally can tell I feel better when I dress in something special when I am performing spells and rituals than when I am doing the same in daily-life outfits, because I am already manifesting before I dress up.