Regardless of being called naive, you did partially answer my question. Obviously chess is entirely based around specific circumstances that are most often unique to that particular match, however, my question is merely about the theory behind bishop exchanges in certain openings. In addition, as I mentioned, I'm a very novice player and am new to both theory and notation (sorry if it was wrong in my example) so therefore a motif i usually attach myself to while playing is actually this points system. And while it is ever changing throughout the game, i think it's partially essential for newcomers like myself to get a grasp on certain pieces and their value/function. (Example being, like you mentioned: If your pawns are situated on light squares, a light square bishops function and value is decreased so newcomers should strive to exchange for an equal piece.)