They said it was a necessity so that development on the game could continue at all since they claim that without the support staff provided to them by Activision it would be too costly for them to maintain older content.

All that means to me though is that maintaining old content was expensive and Bungie thought it would be more profitable to abandon that content, not understanding the long term negative consequences that action would have for the game’s playerbase and reputation.

What’s ironic is that for the last few years they’ve even been removing so much of the older content that by the time they do release the final expansion new players will only be able to experience the last quarter of Destiny’s story.