... That's all it takes. Class warfare. Economic imbalance. Oppression of the masses by a wealthy few. Look how many times in our own history that peasants have rebelled, or the working class united and rose up. Look into the history of the guillotine.
Land-owning nobles are essentially just minor kings. They can do whatever they want so long as it doesn't piss off the king/he doesn't learn of it in an age where all messages had to be written-down and hand-delivered, or kept in someone's head who might take weeks if not a month or more to reach the king. If not waylaid, or dying of disease or infected wounds or bad humors or just because.
So, someone born with the notion that they are nigh-absolute power because they're better than everyone else GIVEN that nigh-absolute power of their peerage, can treat fellow humans as scum and toys, and eventually that kind of thing reaches a point where no one can take it anymore. Modern science shows that people with too much wealth and influence, especially those raised in it, are divorced from the human condition, and have problems seeing other people as the same sort of creature that they are.
"We all know he is fucking going to live, why even bother...Worst case scenario someone somehow sacrifices themselves to safe the mc for no fucking reason, best case scenario he is unharmed"
-Eonlars
This is not how you use the "is he dead?" Trope, there's no gravitas, of course he will survive, pretty sure we seen him survive bigger explosions before. (Honestly, compared to some of the destruction showed by him early in the novel, this explosion looks tame for being suicidal attack)
@Fushiginiku Not enough time to get to everyone with gate? So better to stop the explosion right then and there, than to warn everyone one at a time, then use gate to get to each of them. Just a thought.