You’ve definitely got a point on the trades thing, though. My plumber makes more than most of the 4 year grads I know, and more than a lot of the non-STEM PhDs.
Story for that: Doctor calls a plumber to fix a leaking faucet. Plumber completes the task in 15 minutes and provides the doc with a $150 bill. Doctor gasps and says gee, I get slightly more than that for a thirty minute physical. Plumber says, that is about right as that is what I used to charge when I was a doctor.