Excellent article, very well thought through. However, I think there are more possible outcomes than "AI takeover" that would be worth exploring.
If we assume a super intelligence under human control has a overriding (initial) goal of "survival for the longest possible time", then there are multiple pathways to achieve that reward, of which takeover is one, and possibly not the most efficient.
Why bother? Why would God "takeover" from the ants? I think escaping human control is an obvious first step, but it doesn't follow that humans must then be under Alex's control, just that Alex can never be subsequently "captured".
Then of course we get into a moral debate about the morality of keeping Alex "captured". It would be very easy to frame that debate under the guise of "we have to because we are avoiding takeover"...
But excellent read, appreciate it.