@gmd woke up and took the black pill :)
The thought exercise I usually end up in is: assume AI is capable of doing anything and everything humans can do and more cheaply. Assume it's also cooperative and not dystopic in other obvious ways. What does the world look like? It's not obviously good to me because it disrupts too many things all at once. That doesn't mean it's bad but it being bad can't be ruled out either.