Well, the endgame of that radicalization will be hangman's nooses being put up in the Capitol, last time the people putting it up were too stupid and led by a moron, but if they let it continue, someone half competent might try to come at them as well. They don't live that far away from society that if they let it catch fire, they won't get burned.
The point is that societies could progress past it, that it's not inescapable.
So the fact that there are still absolute monarchies does not invalidate that societies that are better are possible, like most of our societies today.
Every empire seems unassailable and eternal, until it doesn't. The USSR seemed like it will last beyond our lifetimes, until it didn't.
What exactly were you expecting from Ubisoft?