I just can’t get behind the idea that there is any one specific way to play this game and all others are invalid. Look at the difference in opinions on Suit Only. In a normal mission, there is a reward for completing a map Suit Only but the reward is higher for actually changing disguises. Is it better, reward-wise, to play Suit Only or not?
You can say that canonically Agent 47 has never killed a non-target and insist that every player accept that is part of 47’s character, and on that point, you’re correct. The game even penalizes the player for killing non-targets, which is a clear indication that it’s not something the player is supposed to be doing.
Yet there are specific challenges and rewards for doing things that 47 is not supposed to do. Why reward the player for taking guards and other non-targets out with assault weapons if the player isn’t supposed to do so, at least for that challenge?
You could argue that there should be one “perfect” time where every player does exactly what 47 is “supposed” to do and nothing else, but to say that every single time I play the game I must do that and only that is clearly incorrect.
In Freelancer you get a trophy for failing a mission. You get another trophy for failing 10 missions. You cannot simultaneously play the game 100% perfectly and get those trophies.
It’s fine to say that there is one ideal play style that all players should use at least once, but it’s not the way that every player should play all the time. I happen to enjoy killing off non-targets from time to time, whether 47 would do so or not.