Just look at the education institutions - especially trade schools.

30 years ago, my uncle was hired off the street to be an electrical lineman with no priors...in small town USA. He was making top dollar within a year.

Now to get the same exact entry level position, they want you to fork out $50,000 (typically debt for most folks who would actually go for the job in the first place) for two years of schooling. Electrical line work is not rocket science. It doesn't require two years of schooling to do it. It's a lot of hard labor with a bit of knowledge you can pick up on the job.

Welding, machining, maintenance, same boat. Almost all of the private for profit trade schools are more expensive per year (before living expenses) than a basic public university.

They're all scams. Little to nothing has changed in these jobs besides machining (CNC...which can also be taught on the job) and they were almost exclusively OTJ training 30 years ago.

Rich people set up the institutions to make profit, then the businesses (also run by rich people) decided they wouldn't hire to train.