How many Stanford students are even capable of working a trade?
Yes! People take "simple jobs" like hauling trash or cleaning sewers or welding pipes because it's stress free! Unlike those high-stress jobs at Facebook where you take the free party bus to the office, get free food, drink, gym, yoga, and massages, and even have internal message boards where you're encouraged to post about how horrible you're being treated. So stressful! I bet all of those 10xers at the FAANGS wish they could be maintenance workers.
For every person working at a FAANG you can probably find 1,000 working in a place with the same shitty working conditions most people are subjected to.
As a counter example cops can make $200k a year doing detail work (standing around) and retire with a pension after 20 years. There are similar situations (with lesser pay) for a lot of city and state level civil service.
There are shit jobs that will wear you down in every field. They're the jobs most people are working.
"How many trade workers are even capable of going to Stanford?"
People like to talk about "grit" in white collar circles. If you want to see real "grit" go talk to the blue collar people who do shitty jobs at the expense of their personal health so their kids can have a better life.
The working class has an understanding of self sacrifice that is largely absent from more well-off groups.