The mining change in this patch restructured the whole pob economy that existed before most of the currently active pobs are those that produce equipment or refine ore.
A lot of the now decaying ones are doing so as they lost the purpose that made there owners work them. Equipment especially the cloaking and jump drives have been made more harder and expensive to get with the Uncharted/Earhart materials and this is without mentioning the code weapon/equipment crafting.
The price on those materials required are steep especially the capital ship guns. That also contributed to the number of abandoned pobs.
As for the ones decaying in House space the Governments can destroy them if they want.
In my opinion this is a improvement especially the distance from npc bases.