This is just my own observation, but the tradesmen I've seen do OK in the US are those that own and run their own business -- even those that have just 1 tradesperson working. Think "Inland Plumbing LLC" run by a guy and his wife out of their house. Yes, many trades are back-breaking work. I have a relative who was a home inspector for years (crawling around in attics, crawl spaces, and roofs all day is exhausting), and he did struggle at times to pay to raise several kids.
Owner-operator electricians and plumbers in particular (and especially those rated for commercial work) can do very well.
You only see the 58yo that comes to unclog your drain. You don't see the 58yo who's name is on the van. You don't see the one who has some comfy job as a building manager for some commercial facility.
The trades are not without their issues, however. Many of them are physical jobs. The trades people who have come to work at my house, if they're my age (58) are hobbling and broken. Their hands look like hell. Many are sunburned. Many if not most of them work for tiny businesses that receive virtually no oversight.
Encouraging the trades might make sense in a country with a strong safety net, free health care, better labor laws, stronger unions. The American public figures who are promoting the trades also tend to be doing nothing about those things, or are even opposed to them. I've heard that the trades are a good option in Europe.