The reason that no one involved in the game's development objected to the word "warfighter" is that the U.S. Defense Department has used "warfighter" as a standard term for military personnel since the late 1980s or early 1990s: Thus Earl L. Wiener et al., Eds. Human Factors in Aviation, 1988

Warfighter is literally the Department of War's Amazonian or Googler or any other cringe term you'd see in company PR or recruiting material.