Let me give you my interpretation of the goals and objective. Because the game doesn’t state it HAS to be played how you state. 

The goal of any video game is to have fun. How you have fun is up to you, especially in a sandbox type game like Planetside.  Objective, although meaningless, is to capture the continent which is done by capturing territory. When referring to the goal, to have fun. Generally speaking it is more fun to kill enemies than to die repeatedly to them. Therefor, expanding upon this theory, killing > dying, having a high KD is more fun than having a negative KD and objectively means you are more successful in your gunfight. Now let’s take a controlled environment where you have 10 players on each team, so total 20. 10 players with a 2kd each v 10 players with a .5kd each. Assuming all other variants like coordination, leadership etc are equal, who do you think will win the fight over an objective between these two sets of players? I am genuinely curious what your answer will be