> I think one form of cognitive labor will remain: What do we actually want to do/build.

Sure, but you don't need very many people to do that relative to the billions of workers that currently exist.

If you wipe out 90% of all jobs instead of 100% the practical implications for society as a whole are roughly exactly the same.

The Great Depression was "only" 25% unemployment.

A good precedent is mechanized agriculture. When machines effectively replaced most humans in agriculture, unemployment did not rise to 90%.