The same thing that happened in the year before Destiny was released. A lot of content doesn't exist any-more. The whole thing with what happened the year before Destiny is filled with a lot of suspicion, misinformation and theories. I looked up as much information that I could find and from what I can tell the most popular theory is that Activision wanted Destiny to be released before it could be fully finished, leading to cuts and total reworking of the story and cuts in multiplayer mechanics like trading and such. Can't tell you if it's true and I won't post articles to the posts I think are true out of fear of breaking forums rules. Look up some videos online about it and see where that takes you.