I have read the post-scarcity handbook carefully, and taken notes for use by my PCs in other games. It's very well researched and written.
This game is intended to hold onto a medieval or legendary flavor, which is opposed to post-scarcity. We are approaching a time similar to the fall of Rome or the death of Charlemagne, not the Renaissance or the Industrial Revolution. It's like Sauron is about to organize the orcs, or the White Witch is started her eternal winter.
The underground cultures and other planes are about to re-emerge. There will soon be an influx of monsters and Chaotic cultures from other planes, and the civilization will be under siege. It will be struggling to defend itself, not growing economically.
This is the dawn of an Age of Heroes, as they struggle against the rising tide of invasions from forces of Evil and Chaos. There have been Ages of Heroes before. NPCs will rise in power and levels at about the same rate that the PCs do. Soon, the highest level characters will be the ones spending all their time facing the monsters, not sitting at home researching.
Lord Angmar is designed to be able to understand threats to his realm, but not to be able to defend it against them without the PCs.
Yes, there was no way to know all this. I tried to give all the information relevant to creating Angmar, and no more.