I'd summarize that as: civilization has always featured the few powerful having control over the many, but those few still had to satisfy at least some people.

I'd summarize that as: civilization has always featured the few powerful having control over the many, but those few still had to satisfy at least some people. AI that can closely mimic humans and does not have a concept of self-benefit could vastly increase the power that individuals are able to wield, even beyond the kings and dictators of the past. Contrary to your assertion that it isn't a "runaway" scenario, it very well could be one; it's just not the AI that's leading the charge. Fairly similar idea to Vernor Vinge's concept of how the rise of a powerful surveillance state could be a civilization-ending event, by conferring unprecedented power into the hands of a few.