Star Dragon City, despite having spent over a year essentially completing the process of "de-undead-ization," had achieved this under the difficult circumstances of reduced production and consumption.
In such a situation, development and progress also became extremely difficult.
They wouldn't starve to death, but one could forget about seeing new changes every day in their territory, as had been the case during the Undead's presence.
The developments of Star Dragon City over this past year make it clear that without the Undead, it's really difficult just relying on the local people.
The Undead themselves are a resource.
With their return, Star Dragon City gained a batch of cybernetically enhanced laborers, with livers on their backs — they don't complain about hardship or fatigue, and while they earn little, they also have significant spending power, purchasing items without considering practicality.
Such types of residents are simply perfect.