This novel is based on some great concepts, but overall I don't think it did enough with them.
The premise is that the inhabitants of a post-apocalyptic future have the ability to communicate with the past, which creates alternate timelines that they can continue to communicate with. They can recruit people in these alternate timelines (which they call "stubs") to control drones in their present, including humanoids that they call "peripherals".
This seems like a setup to explore wealth inequality and imperialist exploitation - the stub would be labour-rich while the future is depopulated - and it does have an element of that. However, it is portrayed more as a hobby, an intellectual exercise to see if anything can be done to avoid the apocalypse in the stub by making advanced technology available to it. The action of the novel is incidental to the nature of the stub or its relationship to the future - an accidental witnessing of a murder which makes it a battleground between forces that are alien to it, over matters that don't concern it.
In the end, this rich-man's fancy is unambiguously beneficial to the people living in the stub, and that's where it's left. Yay billionaire philanthropy, I guess.
I also found it quite difficult to follow what was going on initially. It starts out with one of my pet-peeves - a "game" that does not seem like something that an experienced gamer such as the protagonist would plausibly find entertaining: flying a drone around and bumping other drones out of the way for some unspecified reason. The TV show does much better with this by having the neural control tech for peripherals available in the stub from the beginning, and having it used in a way that could plausibly be an action-adventure game. But, this isn't a review of the TV show :P