What is the next large labour-absorbing sector supposed to be?
If anything, it will be the trades. We're still a solid time away from being able to replicating what muscles and skin do - and fundamentally, there will always be a need for someone to run cable, terminate wiring and unclog a sewer pipe. At the same time, the trades are desperate for staff after the "academization" push of the last decades.
It won't be one large one, it will be thousands of little ones.
Every time this happens throughout history (and I mean going all the way back way past industrial revolution, to dawn of agriculture, to the earliest documented history, to the mitochondria, to the earliest stars exploding...) the result of a better way to get work done is more complexity and more diversity in work done (processes for increasing entropy).
The author said not to confuse laws of nature with observations of history, and I take issue with the implication. My perspective is grounded deep in physics, chemistry, biology and anthropology and after spending 10 years fretting over what AI would do to our civilization this decade I am not worried about labor displacement.
What I am worried about is power struggles and brainwashing.