Hercules
The biggest problems we have with lots of people living in cities is due to poverty. Hopefully, with a stable population of 9 billion, and a century or two of economic growth, we can develop away from that damaging poverty.
Actually, the biggest environmental problems do not come from city dwellers. Sure, the problems are more concentrated in cities, and we see greater problems per acre. But it is away from cities where the greatest harm is done, though this harm is spread over a much greater acreage. Deforestation. Soil loss. Farm pollution etc.
to eliminate poverty we are going to have to make more people prosperous, which
should be self evident, therefore if we are all going to be consuming more
resources. and where are these resources coming from: forests, oceans,
farmlands. which means more destruction of the environment.
humans are essentially selfish, aggressive, greedy, self interested foraging animals,
who care little for their habitat with a slash and burn lifestyle.
The idea that an addition 3 billion of these creatures to the biosphere
is going to be anything but a disaster for the planet flies in the face of
all the evidence so far. To imagine that somehow we are all suddenly
going to become peaceloving, altruistic, fluffy little fairies is fantasy.
Sooner or later the population is going to come down, in nature this
is usually accompanied by a catastrophic sudden decline brought
on by environmental collapse or disease. the is no evidence we are
going to behave any differently, we will suffer a similar fate. technology
is not going to save us unless we use it to scale back the population,
but with a new global order and a one world economy based on consumption
there will always be a need to overpopulate to sustain growth. We are
doomed, save your own skin while you can, if you can.