And once there isn't, chances are no unaugmented human will have a say in what happens next. Their productivity would be so low in comparison that they can't even revolt efficiently.

History is not a useful comparison as the past elites weren't that much smarter than their followers. True higher intelligence is an insurmountable opponent. Numbers usually don't play a role when facing a sufficient gap in knowledge and technology.

A well-educated human is valued at hundreds of uneducated humans today, at almost any task, civil or military. I have no idea what an intelligent entity with a brain/processing hardware of the size of a skyscraper would be valued at. It might be able to stop any and all attackers just by talking to them after reverse-engineering their thought patterns, or by creating a virus that kills them, or by manipulating some of them to fight the rest, or by altering society to depend on it, or any of millions of other methods.

Bottom line: we have little idea what happens if machines surpass humans in general mental tasks. It's quite possible that the first one undergoes an intelligence explosion and seals the fate of the solar system or more. If that happens, I just hope the person who programs it chooses the goals wisely.