Of course, if you assume that AIs will be able to do whatever they want without any resistance whatsoever from us, then you can of course conclude that they will be able to achieve any goals they want without needing to compromise with us. If killing humans doesn’t cost anything, then yes, the benefits of killing humans, however small, will be higher, and thus it will be rational for AIs to kill humans. I am doubting the claim that the cost of killing humans will be literally zero.
See Ben’s comment for why the level of nanotech we’re talking about implies a cost of approximately zero.
I would also add: having more energy in the immediate future means more probes send out faster to more distant parts of the galaxy, which may be measured in “additional star systems colonized before they disappear outside the lightcone via universe expansion”. So the benefits are not trivial either.
See Ben’s comment for why the level of nanotech we’re talking about implies a cost of approximately zero.
I would also add: having more energy in the immediate future means more probes send out faster to more distant parts of the galaxy, which may be measured in “additional star systems colonized before they disappear outside the lightcone via universe expansion”. So the benefits are not trivial either.