Since this aspect of the game is how Bungie and publisher Activision are milking extra cash from players they have likely designed the game to encourage players to pay more, and they did this by slowing down XP earning rates behind-the-scenes. That was an intentional design choice and arguably a misleading one. Instead of the levelling progress bar filling out at a normal rate, players rigorously tested and discovered that Destiny 2 was cutting the amount of XP earned for activities completed cl...