I just don't understand why the author would have decided to create drama by making it so that nobles harbor a mindless, unconditional hatred for commoners. In reality, it's not that easy to hate every single member of a certain group that you interact with on a regular basis. Imagine if regular people were actually overtaken by intense rage every time they came upon anyone of another race. Society would literally cease to function. Imagine if instead of enslaving African natives and exploiting their lives for profit, Europeans just tried to kill as many of them as they could. That kind of shit just doesn't happen outside of religious extremist groups. (Edit: I forgot about Hitler, but there's no way he would've spent government money to create a prestigious school that smart, talented Jewish people could get into as long as they didn't mind being viciously harassed by other Germans. Not to mention, there are no Jewish people who would attend if that were the case.) The nobles have nothing to gain from antagonizing commoners, and, from the looks of it, they've already reaped the karma of their own actions. Why repeat history? Nobles are supposed to receive a better education than commoners, right? If that's the case, why are they all so fucking stupid? Desir isn't even smart. It's just that all of the antagonists are neanderthals.
Maybe the academy only teaches students how to perform magic, and nothing else. That might explain the terrifying lack of basic intelligence that people in this world seem to exhibit. If I didn't know better, I might have thought this manhwa was written by a Chinese xianxia author.