Game and dlc licences are controlled by the platform you bought it on not by Bungie.... and they don't like to share. When you purchase a game, dlc or in game currency a percentage of that money goes to the platform provider. When you switch platforms that new provider wants their share of the money before allowing you the necessary licences. If Bungie covered the cost for all platforms it would cost more than what you paid. Season passes and dungeon keys are pure in game purchases so are controlled by Bungie and to allow them to transfer to other platforms are locked to the active characters on the platform you purchased it.