alt Hacker News>loads of people have historically done giant pivots at midlife
Lots of people didn't have their field automated away though alongside most other knowledge work fields, or seen at the same time a drop in demand in manual work and an oversupply (drop in demand because of upcoming AI layoffs, and oversupply in manual fields, because of same)
Everyone can't be a plumber.
In fact one of the worst "trade offs" of the trades is they can very much be a young mans game.
It gets real hard to sling water heaters up/down tight stairs or pull cable in a 100+ degree attic into your 50s.