Source: https://www.youtube.com/watch?v=y5DGyG6Qwvk&t=430
[7:10] Ed: What is the backround sim?
Dav: So, to us the whole point of... the background simulation, is to try and bring the galaxy to life.
[7:53]... it also lets players interact with each other,
kinda indirectly, trying to push in same directions or indeed in opposite directions, without ever actually seeing each other directly in space and breaking out the laser beams.
Source: https://www.youtube.com/watch?v=VCy1ZYjLvdQ&t=862
[14:22]Adam: It's a big question, what is the background sim... at it's core it's supposed to represent a simulation of the humanity in our game... it's supposed to represent how players action's impact that world around them,
so we're talking about actions from players no matter what platform or mode they're on, it's all part of one shared galaxy.
Source: https://www.youtube.com/watch?v=U0zBtQcdHvs&t=642
[10:46] (after listing the different types of simulations going on)
... these are all background simulations, they are designed to bring the galaxy to life based on player activities.
They are not necessarily intended to be the end goal in and of themselves, they are supposed to enrich the game using gameplay loops that are a little more immediate... these are a little more immediate, they work in concert,
they work across many different players on many different platforms in all the different game modes, so, they're bringing the galaxy to life.