Treating the anecdote as a legitimate rebuttal, I can only assume the meaning of the passage is that completely economic disempowerment of most humans is a non-starter because those humans will thus have no money thus there would be no economic incentive for universal automation/disempowerment.

I believe this is a fallacy. It's like saying that the dog food industry shouldn't exist since dogs don't have any money to pay for it. What I mean by this is: the economic utility of dogs is so insignificant that any economic activity that happens to benefit them will not be by their choice. Did the sudden unemployment of millions of horses prevent the rise of the car?