Well that depends on the nature of your story doesn't it. Edward Rutherfurd might tell you a story that spans 10,000 years. Isaac Asimov might tell you a story that spans 50,000 years or more. In that context, a hundred years or so in this game is nothing.
And yes, there are in fact novels, movies etc out there that end unsatisfactorily with the lead characters accepting the normalcy of their existence, knowing that their future will just be more of the same. It is a common cynical trope amongst indie films and novels.
So to an extent, your suggestion that books and stories provide the ideal narrative example for this game, is in fact flawed - as there are examples that directly contradict the idea that a classic 'end' is important, or even desired.
Perhaps the lesson of Bannerlord, is in fact a meditation on the futility of human violence, that it begets more violence. and more. and more. without end.