Because DC doesn't have a crossdressing male hero that I know of. Men don't just wear skirts in our culture unless they're part of a more particular subculture - drag, lgbtq, etc. Which honestly there should be heroes from those groups. But I don't know of any, so therefore don't want any of the heroes not from that scene/background to suddenly start crossdressing, it'd just feel like something that comes out of nowhere. It's fine if it's not something appealing for you, but I think it's wrong of you to suggest that it shouldn't be appealing to us or that we're rooted in some kind of antiquated "gendered thinking" for wanting to see it - frankly, it just feels like you're skirting around wanting to call us sexist for preferring this one fashion choice for one hero.