During the quest, you find out that the message was sent before the Traveler’s arrival in our solar system.
Jazzy has already made note of this, but it’s not the message that was sent pre-Golden Age. The quote is this:
“So it turns out, both the music and the quotation, predate the Traveler’s arrival in this solar system. They’re old.”
This, paired with the fact that the boxes use the Warmind logo and that one file was updated in real-time, point towards an active presence. Additionally, Rasputin has in the past used old music and quotations in our interactions with him. He’s referenced both The Brothers Karamazov and Anna Karenina in the past, both being pre-Golden Age.
Remember, Rasputin is fragmented according to the lore.
Where is it said that Rasputin is “fragmented”? He was assumed dead, yes, but that is not synonymous with fragmentation. It’s said that the network fragmented, but Rasputin was not the only Warmind in the network.
[The Cabal] are running away from something, which is most likely the Darkness.
We don’t know why the Cabal are on their crusade, aside from cultural significance. It was speculated in Destiny 1 that they were fleeing something, but that’s one Ghost’s guess. It’s possible, certainly, but far from confirmed.
The only thing [the Vex] can’t simulate is our Light.
They also can’t simulate Warminds, which is how the Ishtar Collective managed to escape the Vex simulation they found themselves in:
ESI: …we call for help.
SUNDARESH: That’s right. We bring in someone smarter than the specimen. Someone too big to simulate and predict. A warmind.
SHIM: In the real world, the warmind will be able to behave in ways the Vex can’t simulate. It’s too smart. The warmind may be able to get into the Vex and rescue - us.