There is a difference between education and job training.
Sounds like your example got a good education but ultimately all he really wanted was job training. He got that and was happy.
I would say he probably uses those high schools subjects every day, just doesn’t know it. They’re inadvertently disguised as something else.
I’ve known carpenters that used geometry without ever being taught geometry. And they didn’t know they were using it.
I’ve messed with kids’ heads when they couldn’t do simple math. They apparently weren’t even pressured to learn multiplication tables by rote. If 7x5 was a problem for them I’d ask them what 3+4 was. They can usually get that. So (3+4)5=15+20=35. They’ll give you a blank stare. Then you move on to integral calculus...the integral from 0 to 5 of the function f(x)=7.....
‘I would say he probably uses those high schools subjects every day...’
I can guarantee you I have not used Plane Geometry nor any of the lab sciences I studied in any real workplace...