That’s the crazy part. It would be so easy for Hikaru to gradually meet women who don’t fit the general feminine mindset and realize that just because he needs to be a girl, doesn’t mean he needs to be a girl. Like, maybe he finds a way to perform all his kunoichi skills in his own personal way.
But I don’t think the author wanted to write a manga about seriously exploring gender roles in society, they wanted to write an ecchi manga.