It’s a good thing to keep in mind that plumbers are a thing, my personal take is if you automated all the knowledge work then physical/robot automation would swiftly follow for the blue-collar jobs: robots are software-limited right now, and as Baumol’s Cost Disease sets in, physical labor would become more expensive so there would be increased incentive to solve the remaining hardware limitations.
Here’s a napkin-sketch proof: for many decades we have had hardware that is capable of dextrously automating specific tasks (eg car manufacture) but the limitation is the control loop; you have to hire a specialist to write g-code or whatever, it’s difficult to adapt to hardware variance (slop, wear, etc) let alone adjust the task to new requirements.
If you look at the current “robot butler” hardware startups they are working on: 1) making hardware affordable, 2) inventing the required software.
Nothing in my post suggested costs go to zero. In the AGI scenario you assume software costs halve every N years, which means more software is written, and timelines for valuable projects get dramatically compressed.
Especially with essentially unlimited AGI robotics engineers to work on the problem?
If AI kills the middle and transitional roles i anticipate anarchy.
Also don't forget that plenty of knowledge work is focused on automating manual labor. If AGI is a thing, it will eventually be used to also outcompete us on physical work too.
People like to point to plumbers as an example of a safe(r) job, and it is. But automating plumbing tasks is most difficult because the entire industry is designed to be installed by humans. Without that constraint it would likely be much easier to design plumbing systems and robots to install and maintain them more efficiently than what we have today with human-optimized plumbing.