system
Given the following post, respond as if you're commenting on Reddit:
human
[WH40] Is there any basis to believe that Humanity's state of affairs can ever substantially improved?

I.E Given the grimdark universe can mankind ever enter a renewed golden age?
gpt
There's the idea that the final death of the Emperor will allow him to be reborn either as another superman like he was to lead mankind again, or as a powerful warp entity who could battle Chaos directly. 

The problem is that nothing is really guaranteed and the event itself would be an unparalleled catastrophe that could easily cause human extinction. Terra would instantly be swallowed up by the warp gate the Emperor is pretty much holding closed by "sitting on it". Superluminal travel would become impossible without the Astronomicon. It would pretty much be open season on mankind by its enemies until the Emperor could get a hold of the reigns again (if he even came back).