All due respect, Dekker, but WHERE do you get these terms being used for THOUSANDS of years?!
Last I checked, the Romans had centurions, pilus priors, primus pilus, tribunes, and the like.
These words trace their origins (disregarding Latin roots that had NO military usage) at most back a thousand years- and even then, they were NOT used in a military context. In that regard, they are at most hundreds of years old.
To say that NOTHING will change is to disregard the entirety of military history, which has shown nothing BUT the fact that the armed forces of the world will continue to evolve, adapt, and change and will come up with new terms, ranks, and forms of address to do so. To insist that just because a certain way particular to a particular time and region/language will last simply because it is what you identify with is ridiculous.
The dev team is, as far as I know, creating a work of fiction based off of a work of fiction- not a perfect replica of what you consider 'appropriate' military protocol.