Industrialization allowed people to shift human labor from agriculture to factories and such.
Seems like intellectual labor became more possible as people looked beyond subsistence but also more valuable since a greater population could drive demand for more than just subsistence related activities.
If both aren’t done by many humans, what’s left? Sports training and massage therapy? Sports training might not even be safe…
OTOH, my current lifestyle is already weird if I think about it. Developing software for a machine that I cannot make myself, whose raw materials I cannot obtain, using energy I cannot produce on my own — somehow entitles me to get a particular amount of goods and services from others including food, healthcare, entertainment, landscaping, and manufactured goods.
We live in interesting times…