Actually imagine the most terrifying possibility.

Imagine humanity's last creation was an AI designed to simulate internet traffic. In order to truely protect against AI detection, they found the only way to truely gain perfect immitation, is to 100% run human simulations. Basically the matrix, except instead of humans strapped in, it's all AIs that think they are humans, living mundane lives... gaining experience so they can post on the internet just looking like real people, because, even they don't know they aren't real people.

Actual humanity died out 20 years ago, but the simulations are still running, artificial intelligence's are living full on lives, raising kids, all for the purposes of generating shit posts, that will only be read by other AIs, that also think they are real people.