I personally am loving how the gender roles are meshing more and more as time goes on, particularly in the arena of fashion. The fact that guys can wear bright colors, skin tight clothes, and makeup is a beautiful thing.
It does not dismiss gender identity at all to me, if someone wants to wear make up as a trans-man.
Even if someone wanted to dress as a woman, as a trans-man, it wouldn't make a difference.
The whole point of being trans, is you identify with a different gender.
If you still want to be a man, even as fashion is becoming more and more unisex, it is simply making the point that gender is something separate from the cliche societal roles that people tend to define it as.
I don't personally wear it, but I did a lot as a teen, and was mistaken as a boy more often. lol