Presumably-otherwise in a disaster like this, robotics would have been one of the first thoughts for recovery.
We're humans: at some point, someone is going to get the bright idea of trying to take their neighbor's stuff. And usually, there is some sort of warlord figure driving it. That's what I meant by "Emperors". Someone trying to unite the galaxy under themselves and being at least somewhat successful-or at least successful enough to affect us. Which is actually another worrying point. We have no idea how long it will be until the Leviathan Gates get activated again. Unlike AoS, there is no reason to assume that it is going to be down forever.
Since the broad strokes of the earlier stuff is still in play, and we managed to make some sort of deal with some of them, I would assume so. Though honestly, Eldar were pretty much Q-entities anyway, with their actual civilization mattering very, very little.
Almost certainly given that something managed to hit both Mirande and Dia, forcing them off of the stage. Either that or the Reavers have significantly expanded capabilities than even the Eldar, which is a rather horrifying thought.
...
I dearly hope that there are other immaterial predators than the Reavers, or we are in a shit-load of trouble. Regardless, something to figure out.
And here, I think, is where our policies differ. In my opinion, you desperately need to know as much truth as you possibly can in a C'thulu setting. After all, what you don't know most decidedly can hurt you, and insane is still better than dead.
Edit: Realized I had gone full Italian there. Also, a scary thought: If the Reavers are even more powerful here,
what exactly were they fighting to cause this hellhole?