And visa versa, when the distribution of wealth tends toward justice the population tends toward ideal sustainable levels.
It's all relative.
The effect works at the macro and micro level within communities too.
The communities not receiving justice will grow or decline unsustainably. The ones getting justice will find the ideal level in that time and place.
If there's a genuine population crisis in any time and place, it will always be because that community has chosen injustice over justice.
There's an easy remedy.