Change is welcome, the game's getting stale. Old weapons have their place, raid weapons have abilities to help with their relevant raids and old weapons can still be used in pvp but will be worthless in iron banner. I wouldn't be surprised if some point in the future, maybe in destiny 2, we will actually get the ability to ascend some old weapons. I'd imagine this would be in the form of a "loyalty bonus" of some sort i.e. in game consumables (1 armour piece and 1 weapon). It would move the game forward but still reward day one players.