I once heard a quote from the screenplay writer of Braveheart that went something like, "Don't let facts get in the way of the truth." Sounds like a dumb thing to say, I know, but there is a tiny kernel of wisdom in there. It's easy to get so hung up on minutia that we miss the big picture. With that in mind, it becomes a lot easier to make a biographical video game. Developers don't have to agonize over exact dates, names and numbers so long as they capture the spirit of events. In truth, some autobiographical memoirs such as those dictated by Napoleon Bonaparte and Otto von Bismark don't exactly jive with historical facts so there's that point to consider as well. Before moving on I'd like to state for the record that my first pick for a biography-themed video game would be Lucius Quinctius Cincinnatus, or if it had to be an American, George Washinton. For the sake of continuity though I'm going to use Chris Kyle for my hypothetical example.
Sounds rough, I know, but such was the life of America's most prolific military sniper. Walk a mile in his shoes, or in this case play a video game about him for a couple of hours, and you'll get a better understanding of the life he lived. Would it be a 100 percent authentic experience? Of course not. In fact it might drift into "what if..." territory. Since movies and TV don't shy away from using artistic licenses though I don't see why video games have to avoid them. An "inspired by true events" label somewhere in the opening segment is all that's necessary, IMO.