Why on earth this trope is so rare.
I realize you're probably being facetious, but I also feel, as an aspiring writer, this deserves a bit of an explanation.
The other Otome Villainess stories tend to be a decostruction of the Otome game genre. Basically, the Author/Mangaka is saying to themselves...
"Okay, the idea that this one girl of a low-born status subverting the hearts, minds, and politics of these people does not make sense. These are the young men who will be the stewards of their country. So what would have to happen for this to actually make sense?"
The answers they come up with vary by degrees. But in general, these are degrees along an axis with one end being "These royals/nobles are absolute garbage" and "the so-called heroine is a manipulative piece of shit".
Many of them come together in the middle. Two excellent examples of this are
The Splendid Revenge of A Super-Dreadnaught Villainess and
The One Within The Villainess.
But this story? It's a deconstruction of a deconstruction! Where the author/mangaka took a long hard look at the Otome Villainess subgenre, and said...
"Okay, this is all fine and good. But why on earth would these people act this way? They're the next generation of their country's leadership! Surely they know better than this! So how can I do this in a way that makes sense?"
And their answer? Make them act like actual Royalty and Nobility. These people act completely out of an obligation of duty. Their lives do not belong to themselves, but instead to the people they are responsible for. They absolutely cannot let themselves be swayed by frivolous things.
Have you ever seen the Raffaella De Laurentiis version of
Dune? I'll admit, it wasn't all that great, but it had some great moments. One of those was in the very beginning where Gurney Halleck comes to Paul Atreides for his regular training. Keep in mind, Paul is the son of a Duke - who is just one step below in Royalty in the ranks of the Nobility. It would not have been out of place for Paul to have been betrothed to Princess Irullian, and thus in-line for succession of the Padishaw Emperor, Shaddam IV.
Paul glibly complains to Gurney that he's not in the mood, at which Gurney kinda loses his shit. (And justifiably so!) Here's the entire exchange...
Paul: ...My father sent you to test me, didn't he?
[He indicates Gurney's baliset]
Paul: Music, then?
Gurney Halleck: No music. I'm packing this for the crossing.
[He sets down the baliset]
Gurney Halleck: Shield practice.
Paul: Again? Gurney, we had practice all this morning. I'm not in the mood.
Gurney Halleck: Not in the mood? Mood's a thing for cattle and loveplay, not fighting!
Paul: I'm sorry, Gurney.
Gurney Halleck: Not sorry enough, not yet!
[He activates his shield and attacks Paul, who activates his own shield barely in time]
Paul: [to himself] What's wrong with Gurney? He's not faking this!
Gurney Halleck: Now, guard yourself for true!
Boom. With this, the writer brings home exactly how seriously Paul should be taking his position in the Ducal House of Atreides.
And that's pretty much what's going on here. In just two chapters, the Author/Mangaka has brought home how serious and sober this setting actually is. And they've done an absolutely masterful job.
NOTE: Edited to correct the name of the producer of the Dune film I referenced.