Is that the most effective backup plan that it could come up with? Because it would be pretty amazing if its thoroughly-considered backup strategy exactly aligned with our wishful thinking. It sounds to me like starting with the outcome we hope would happen, and then looking for a reason why it might happen, rather than a realistic examination of what would actually happen when our own desires aren't part of the equation.

Believe it or not, the diversity argument is the main source of hope that I have that AIs won't wipe us out.

I mean, it hasn't stopped humanity from causing mass-extinction, but hopefully the AI will be more reasonable.