However, those quite a bit better places only employ a small fraction of the number of people of yore and require quite a bit more education thanks to automation.

For example: the Natrona Heights steel mill now employs roughly 100 people on a shift vs when it employed somewhere between 5000-10000 on a shift. Automation killed a ton of employment. Those are the kind of jobs I am talking about.

Don't get me wrong. I don't want to bring all those jobs back. They were terrible jobs.

However, claiming that working those kinds of jobs somehow makes people better is quite suspect, at best.

Ok, OP's argument was about workplace conditions, not low employment numbers, and they claimed that conditions stopped being good around 1980 with no evidence to back it up. We are at less than 4% unemployment so it's a very good thing we don't need 100x more workers to do things the way we did them 100 years ago.

I will say, I'm a 100% knowledge worker, and work from a laptop, but hard labor is good for you (within reason). We have all sorts of illnesses and obesity in modern society because our bodies were built for stamina that we no longer make use of.