Some argue that even without misaligned AI, humanity could lose control of societal systems simply by delegating more and more to AI. They would delegate because these future AIs are more capable and faster than humans, and because competitive dynamics pushing everyone to delegate further, until eventually humans have no control over these societal systems.

Delegation ≠ loss of control, though. A principal can delegate to an agent while maintaining control and seeing what the agent does. CEOs and managers do this all the time obviously. So to go from "strong incentive to delegate" to "loss of control", you may need to also argue that humans will be unable to meaningfully oversee what the AIs do, e.g., because those AIs are too fast and their actions are too complicated for humans to understand. (Again, we're assuming these AIs are intent-aligned, so modulo information, humans can retain control over the AIs.)

I guess to me it isn't at all obvious that all humans would in fact delegate everything to AIs when that means giving up meaningful control. First, there may well exist methods to better aggregate and abstract information for humans so that they can understand enough of what the AIs are doing. Second, most humans would probably be reluctant to give up meaningful control when delegating -- e.g., a CEO would likely be more reluctant to delegate a task or role if they have reason to think they will have no insight into how it's done, or no ability to meaningfully control the employee -- and this seems like it should move the equilibrium away a bit from "delegate everything", even with competitive pressure. But unless all humans do so delegate, some humans will retain meaningful control over the AIs, and arguments about gradual disempowerment look more like arguments about concentration of power.