Most species improve their viability by expanding their population. Races, religions, and cultures increase their viability by increasing their numbers. We are the living remnant of increasing numbers. Therefore, it is not surprising that we believe; increasing population increases viability.
However, while we were sleeping the world changed. After a million years nature changed the equation for human viability. Instead of increasing population increases human viability" now "decreasing population" increases human viability?
We consume more because there are more of us. Even if we had zero population growth, we would consume more because each of us strives to live ever longer lives and ever higher above subsistence.
We produce less, because past production depended on non-renewable resources which are becoming exhausted. Less because past production depended on resources which we consume faster than they are renewing. And less because our wastes are making our ecosystem less productive.
While each trend produces expected problems, together they determine the super event -- "total human footprint crashing into global carrying capacity. This event determines our viability.
This human version of this crash only exists when individuals live far above subsistence. Consider:
Process 1) and 2) above make the end event of "total human footprint approaching carrying capacity" more like an accident than a smooth transition. The people involved don't see the accident coming, can not do much to attenuate the injuries during the crash, and when killed can not learn from the experience.
Human viability now depends on our ability to see and understand this changed system. We have to see an un-experienced-event coming. We have to avoid that event by changing a behavior we have never thought of as the event's creator.
In our new environment a rapidly decreasing population decreases human footprint. As the total human footprint falls farther below the globe's carrying capacity the more viable the human experiment? In this new environment a decreasing number of people increases viability.
The globe's change to these new conditions has transpired largely unnoticed by people of earth. Most of us are still procreating as if increasing population increases our viability. Our genetic and cultural imperatives to increase numbers are now lessening our viability.