A lot of the death was due to the introduction of new diseases, so maybe AI is to blame for Covid-19?

Also, in the similie I think humanity is supposed to be the Old world, so I'm really wondering who we're supposed to find and enslave ...

Everybody thinks they're the center of the universe. Sometimes they're right, for a time. When they decide they were wrong, they tear down the old statues, if only to make the new overlords feel welcome...