[goodpoint]

> This could get deadly serious in terms of sustaining complex systems

Citation needed. Of all problems of this planet, underpopulation is not one of them.

[red-iron-pine]

Yeah we don't need more people. Arguably the amount of people we have now is leading to global ecological damage, even collapse.

"complex systems" -- whatever those are; global trade was a thing long before industrialization -- will survive slow declines. Japan is still a modern country even with a demographic decline.