Why so concerned about this being a historical game?
Simply because the game is based on historical medieval warfare. If the game was based on full on Fantasy or Sci-Fi, then the developers have carte blanche to do whatever, but once you confine yourself to a specific theme like historical medieval warfare, the expectation is that the game mechanics will be based on historical medieval warfare.
That being the case, this game, at its core is a historical medieval warfare "Simulation" so of course most people would want things to be as historical accurate as possible. This is why so many people want things like formations or armor that protects as well as armor did historically and other historically accurate depictions at least as far as a game can take it.
Of course, most of us all realize that given to much simulation and things tend to lose the fun factor, at least for most people, so most of us are willing to give up some historically accuracy in the face of fun However, lets be honest, what is fun is a matter of perception different for each and every one of us and that is the crux of the problem. I mean lets look at flight sims. Some people spend thousands of dollars to build a cockpit in their home while others would prefer flight to be arcade-like as as simple as moving your mouse and using the WASD keys. Same I guess goes for the people playing this game.
However, since this game is kind of marketed and quite frankly developed in a fashion that simulates historical medieval warfare, I honestly think the devs should be erring on the side of historical and shooting for as historical a feeling as possible.
That being said, I am more about how the core gaming mechanics work and feel than about any specific setting. For example, I don't feel just because historically, in medieval times, it was a male dominated society, that Bannerlord has to be a male dominated society. I mean Calradia is a "Fictional" setting after all so why can't there be gender equality? On the other hand, only the world is fictional, not the time period or the type of warfare it is based upon so I want the game to "Feel" like the historical medieval setting it is based upon as much as possible.