Defintion of pay to win: Games that let you buy better gear or allow you to make better items than everyone else at a faster rate and then makes the game largely unbalanced even for people who have skill in the game without paying. In destiny purchasing the dlc does not give you better gear, you still have to find/earn it. It does not give you gear faster than people who did not buy the dlc. It does not LARGELY unbalance the game or remove skill as a factor. Iron banner represents 1 game mode in PVP out of 7 and is a limited time event. Competing or not competing will not affect your ability to play through the remainder of the game. In fact rewards issued in the iron banner are not based on skill but complete rng so even if you are constantly owned by 32s you are not locked out or penalized when it comes to loot. So again I say purchasing the dlc is not pay to win.