Justin Truman, general manager of Bungie, has confirmed that they will add Destiny 2: Forsaken to the Destiny 2 Vault at some point in the future. Truman did not reveal a date for when Bungie will add Forsaken content to the Vault but he did confirm that Bungie is looking to keep the Destiny 2 content pool around its current size.
According to Truman the reason for vaulting Forsaken content is to not have “competing storylines” where a character is bad in some aspects of the story and then good in others. Despite these claims, Bungie still has many conflicting story issues with Destiny 2, some of which have been around for a long while now. Destiny 2 still currently uses a Strike of which Cayde-6 is a part of.