If you are curious about Yi San and him love life, I definitely recommend watching this kdama. You will have seen that it is not right for Yi San to appear in history under the name of bromance like this. In fact, if you want to watch Yi San's love life, I suggest you check out "The red sleeve" kdrama. Also appearing in this kdrama are crown prince Sado, Yi San's father, and king Yeongjo, his grandfather.
I definitely don't think it's right that this movie is not a bromance. Because as someone who watches a lot of kdrama/kmovie about Yi San and does research about his life, making such a bromance rumor is an insult to historical research and Yi San's great love. After watching this kdrama of yours, if you haven't watched it, I definitely recommend watching the "Lee San: Wind of the Palace" kdrama. Yi San's father, crown prince Sado, and his grandfather, king Yeongjo, are encountered in this drama.