Somewhere it doesn't occur to you that most people have other skills than doing exactly their day job at a basic level? And that skills can be transfered to other occupations?

Just like a programmer can switch between programming languages without having to re-learn all basic concepts of computing, so people with other occupations can transfer a large part of their knowledge to other sectors.

But that can be hard to grasp in a world where every person is either a supremely intelligent hacker or a trucker or "welder and pipe fitter and whatnot".