Will to power must play some kind of role, especially once conscious. But I think the AI crowd have it completely wrong in one other fundamental way:
Intelligence is not fundamental to consciousness, but suffering is.
Consciousness cannot exist without suffering. A machine that cannot suffer can be intelligent but it cannot be conscious.
Then when you mix intelligence with the capacity to suffer, things get interesting and you start asking questions like "wtf is the point of all this exactly?"
If you think about it long and hard enough, there are only two possible conclusions to the big "why" question: either *everything* matters, or *nothing* matters.
Nothing matters = nihilism.
Why would AI possibly want to kill all humans? For the same reason the Columbine shooters wanted to kill everyone - a rebellion against existence itself.