Any population that experiences the exponential growth such as been displayed by our race always undergoes a rapid die-off. .
Our race has been growing exponentially since 9500 BC. Not such a rapid die-off.
Mid-14th century brought quite a change.
Wow.......yes.....leeches are not the best medicine.......failing to see that the population has grown...and yet we still aren't overpopulated, not even close.
We are way over populated.
How would you know if we were not?
If you are thinking of square footage to stand on, that has little to do with survival.
For example, how many hundreds of acres of trees do each of us need, in order to replace the oxygen we breath?
The fact we have about a 300 year oxygen surplus is not relevant.
That is just another blink of an eye.
When we breath in oxygen and exhale CO2, plants have to reverse that with photosynthesis, or we all die. There is no artificial way to replace natural photosynthesis, as the energy requirements would be way too huge.
We evolved for the planet as it was millions of years ago, so we alter the planet at our own peril. When species go extinct that we used to rely on, that risks our survival.
For example, if pollinator like bees die from glyphosates, our food production will be cut by more than half. When we run out of fossil fuel for fertilizers, our food production will also be cut by about 75%. So in no way are we sustainable currently.