[meheleventyone]

I mean billions of deaths and civilization collapse is probably at the extreme end but still imaginable.

If poor people and poor countries are screwed then that will lead to major disruption in rich countries as we are reliant on them and potentially a large and dangerous climate refugee situation. Economic collapse in rich countries isn't off the table either.

Then there are questions like how much of the current status quo has to change for "our civilization" to have collapsed?