Most “unskilled labor” is heavily skill dependant. You wouldn’t want a chef, builder or plumber who didn’t know what they were doing. And for production: machinists, mechanics and foremen make or break profit with their skills.
So what’s a better name for these jobs?
I did not say you were unskilled or that police were skilled. Everything is relative.
I checked training time at for some of the occupations that OP mentioned. I don’t live in the US so ymmv.
Car mechanic: 1 year. Painter: 1 year. Chef: 70 weeks. Plumber: 60 weeks.
Extra because you mentioned it: Police is 2 years in the school bench and 6 months of on the job training.