Working the lathe is probably not any easier to learn than "vibe coding" or generic office work like customer support or data entry.
The unspoken problem is that it's enormously expensive to re-educate adults to do something different. Adults just have worse brain plasticity and don't pick things up as quickly as younger workers. Some just refuse to learn thanks to the pervasive culture of ignorance that permeates USA.
And adults cost more as well (even just the basics such as food, which children eat less of) and if they have aging parents or kids, have additional responsibilities that distract them from learning.
No one is taking this risk on and why should they? If I was starting a company, and you suggested to me that I should indiscriminately hire minimum wage workers to work in a machining workshop, but first I have to educate them about machining from scratch, you'd be (rightfully) laughed out of the room, because you're dooming this business to failure.
Once you break that link (e.g. skip a generation of a profession), it's incredibly hard to bring that back. It's like losing institutional knowledge, because your genius employee was hit by a bus, or moved countries.