I'm terrified at the idea that society will select the crazies and the violent instead. I wonder why I think that

My real personal "doom" theory is that AI will, err, remove 99.99% of humans, pretty much everyone except for the top 100,000 based whatever fractally complex metric scheme it deems important.

Then those 100,000 get a utopia, the AI gets everything else, and ultimately the humans are just nice pets.