I don't think Kpop bands or David Bowie for that matter are feminine. They are masculine by definition. If they identify as men, they are men and what they do is manly by definition.

You are right that some people want us to fit into little boxes and that we deny parts of ourselves to fit into those narrows definitions. We hurt ourselves by denying those parts of us.

And no one fits completely into those arbitrary definitions. There is something that we do like or are that we aren't supposed to do or be. You practice karate? not feminine. You are tall? Not feminine (notice models are usually tall). You are short? not masculine. You enjoy dancing? "gay".

The list is ridiculously long and equally stupid. And it changes depending on countries and cultures. Or time. I mean, in Louis XVI time, wearing a wig and heels was men's fashion. The king wore them. And he was considered "manly". Napoleon was famously short. Heavy metal bands have long hair and wear earrings and tights. We can go on.

Women have always find attractive all kind of different men. It is only recently that we are allowed to choose (before it used to be arranged marriages by the parents). As you cleverly point out, many women just love K-pop bands and doesn't really care if they are called "feminine" because they know they are not. And it is just obvious they are manly in their personal way.

But men shouldn't need a woman approval to be what they want to be. Neither we need their approval. There would be someone who would like us as we are. So we should focus on being happy of who we are and ignore the haters.