The writing is absolute shit in my opinion. The portrayal of female characters and their experiences in such a setting is done really poorly. For example, when he runs away from his arranged marriage, he says he still has the soul of a man so he must go pursue his dreams. It makes the desire to pursue your dream a gender based idea, when it’s a very human desire. This could’ve been written to be gender neutral and made it show how he has grown over the years due to having such a restricted life. It could've reflected how he feels his identity has changed since he's become a princess. I feel like there's a lot of things they could've done with the idea of gender/gender roles that they don't do here.
Another issue is despite going through many years of restrictive training and education, he seems to lack tact in all areas: his manner of speech, his lack of care for his identity to be kept a secret, and more. If he disliked his life so much as a princess that he would run away, why would he shout his name in front of many people. Why not use an alias? In addition, if he resonates so much with his new female name that he would rather use that as his hero name, why does he overall see his identity still as a guy at heart rather than a more gender neutral perception.
This whole manga feels like a guy who got thrown into a girl's body for one day instead of a guy who has been living as a girl for 10+ years.