I once thought that overpopulation was the problem. Now I understand that over consumption an inequitable distribution of resources it a bigger problem than overpopulation.
Actually some places are seeing populations decline. Affluence leads to a reduction in reproduction. Poverty drives population growth.
Looking at carrying capacity planet wide is too simplistic. Deserts and ice caps have tiny carrying capacity and coastal temperate regions have huge carrying capacity by comparison. It is unrealistic to assume equitable distribution of resources and unrealistic to assume migration will balance population with carrying capacity.
How much of the planet's carrying capacity are we going to allocate to wild life? Right now we sacrifice non-human populations to the point of extinction to support human populations.
You can't put a number on carrying capacity of the planet or any region, there are too many unknowns. What we do know is if there are less people both people and wildlife do better.
TEK