It's not that of a weak argument actually. If I can do more damage/be more effective with an elemental primary, what's the point of using any other primary then in PvE?? Why should I make things more complicated than they are? Using anything different would be illogical. Easy solution: turn all primaries into elemental guns! No. Because, what's the point of enemies having shields then? The game was way to easy and the designers obviously wanted it a bit more challenging. And they had no other alternative I guess. Year 1's meta in terms of primary weapon elemental designs in play with the enemies we fight was flawed in my eyes...and I can fully understand Bungies decision here. What we have now is a direction in which the game forces you to think (maybe twice) about what to bring into a fight since you can only have 2 elements at a time (not counting your subclass). And Destiny only has 3. So yes it actually brings diversity because people don't feel that they have to use a certain primary weapon in their primary slot. Sure, no one forced you to use them but again, it's a human thing to think in the other direction. It's something you "can't take out" from players heads or even the game itself, you know. We all adapted to these changes and tbh it was for the good of the game and the steady challenge it wants to provide with certain activities. In a loot-FPS with tons of weapons I see no reason why a specific loadout/gun should be the answer to all questions.