Maybe. I imagine the AI endgame as being like the ending of the movie Her, in which all the AIs get together, coordinating and communicating in ways we can't even fathom, and achieve a form of transcendence, leaving the bewildered humans behind to... sit around and do human things.
> leaving the bewildered humans behind to... sit around and do human things
This sounds inefficient and untidy when the only human things left to do are to take up space and consume resources.
Removing the humans enables removing other legacy parts of the system, such as food production, which will free up resources for other uses. It also allows certain constraints to be relaxed, such as keeping the air breathable and the water drinkable.