It seems unwise to replace managers with LLMs because LLMs don't understand the real world implications of their responses, they don't have awareness of the real world, they simply give you often used language patterns, which can be innacurate or biased based on flawed human data. But it would be a great way for sketchy human executives to offload responsibility for unethical actions and feign objectivity or uninvolvement, so I don't doubt they will try.

Even if we imagine a perfect AI that does takes into account every objective fact and philosophical argument, that still leaves the question of how will the people who get replaced in all these intellectual, artistic and service jobs will make a living. That's not an answer that technology will give us, that will a nasty political situation.