I clarify:
Let’s say scientists can’t come up with solutions to global problems, AI gets out of control and turns almost everyone into paperclips during wars, and in the 2040s or 2050s, the surviving people (about a few tens of millions around the world or even less) gradually return to the level of intelligence of their distant ancestors?
You’re assuming I’m America, UK don’t have any predators larger than a cat left, all went extinct.
It’s part of why we’ve got a Deer problem and have to manually cull them every now and again