the cause of the collapse was videogame preorder culture and unfettered early access nonsense. In the universe Starsector takes place in, Valve never axed Steam Early Access and never lost their domination of the PC marketplace, so even though humanity grew to incredible scope and scale of power, able to bridge the gap between stars with casual ease and terraforming planets to their suiting with no regard to the economic feasibility of doing so, the reality of the matter is that while the growth of human potential is non-linear, and the growth of the growth of humanity is non linear, the growth of the growth of the growth of videogame developer greed is nonlinear, expressed here as hH^2<S^3, so no matter how much of a headstart human endeavor got (h), steam greed (S^3) will outdo all of the good done by all deeds of progress mankind has made (H^2).
Of course, this dreaded point, at which all good deeds of mankind are outstripped by the greed of videogame developers and humankind becomes a slave to the perpetual scam of AAA videogame publishers, toiling away in fun mines for the rest of their lives, digging through the rock and the mud in desperate search for precious nuggets of fun to try to scam eachother out of with fraudulent early access and Kickstarter projects they'll start with no intention of ever finishing, was never actually achieved. We have made sure of that. In fact, the process by which this terrible fate will be diverted has already begun, and indeed Alex herself has written about it under her pseudonym, Peter Watts.
In the novelization of the real life events chronicling the non-fictional backstory of the collapse of the Domain of Man, it is revealed that mankind's super corporations are already aware of the impending collapse of the world economy, and have planted nuclear devices in the crust of the earth and all worlds colonized by man in the future, along with a string of hidden listening posts at the bottom of the abysses of the ocean along major fault-lines that send out pulses of tectonic energy and record the reverberations, sending their findings to dedicated sentient AI who maps out the exact damage that would be caused by force-detonating the largest earthquakes ever witnessed by man & the subsequent tsunamis that would tear through the continents, calculating the theoretical death-tolls of such a cataclysm (in terms of work-hours lost) while also calculating the theoretical number of work-hours lost to the predatory business practices of big videogame publishers and early access culture in general, this their proverbial thumb on the trigger and permission, nay a duty, to detonate the moment the lives lost to The Big One would be smaller than the lives lost to terrible Ubisoft games bought before they were released, and thus released before they were done.
Of course, the dark truth of the real world that we actually live in has been marked as a Sci-Fi novel, and not a very well performing one at that, by the world over largely due to the parts about the people manning the listening posts developing the ability to read minds, imprinting psychically onto each other, utterly losing their humanity and going on to inspire all of the parts of Bioshock 1 that weren't related to the game's theme of Objectivism, not that Ken Levine was honest enough to come out and admit that the dive-suit entombed inhuman psychic monstrosities were ripped off of Alex IE Peter Watts' work.
Anywho, the men in the white coats are here for me again so if you're interested in reading more,
the book is free as an act of philanthropy by Peter Watts who is secrely Alex who is secretly a smart-bomb at the bottom of the sea