of all the things to get upset about, "the darkness" (which always seemed more like a poetic name for evil than an actual thing) and the fucking exo stranger... really?
If you read the Grimoire, especially stuff from the Taken King, they expanded on it quite a bit without ever explicitly defining it. But if you consider that "Light" is a literal force in the Destiny universe, being what powers all the Guardians space magic, you kind of have to say the same for "Darkness" as well. It's like white vs black magic or the Force in Star Wars - Sith vs Jedi. Fundamentally opposed forces that are a part of the fabric of that reality/universe. The Hive worship the Darkness (or more specifically the Worms, servants to the Darkness), and their Wizards call upon it for their space magic. Various Gaurdians have also been corrupted by the Darkness after being tempted by it's power, so it is most definitely more than just a metaphor for "evil".
Confusingly, it is also clearly referenced as an entity - with attributes described from the POV of Rasputin in the Grimoire - that attacked Earth and the Traveler, directly causing the collapse...
It sounds like The Darkness HAS been defined since he was talking past tense ("at a point"), and is still an important part of the overarching story line, it's just not going to be mentioned in this game... which for a full sequel is pretty puzzling.
This makes me worry they really have no idea where the story is going, which is something I would have hoped they figured out by now. Even with all the last minute changes D1 story went through, I figured by now they had established a firm backstory for the Destiny universe to build on going forward, and the details in The Taken King grimoire seemed to suggest they had.
Or maybe they are just rebooting the backstory completely...
The removal of the Grimoire is kind of a shame. I'm glad they are putting more into the game's direct storytelling, but the Grimoire was super interesting and gave depth to the universe that really can't be replicated by additonal/better cut scenes and dialogue. They really should have kept it and moved it into the in-game menu.
Don't know what to make of "The Stranger" arc being considered complete.... that makes no sense and makes me think they really ARE rebooting the universe in a way.