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?
Untrained labour. There’s skill in unskilled labour, and even a significant amount in certain cases, but it’s the kind you can pick up on the fly. Any actual training is done quickly enough random shitty employers will take a loss on it.
It doesn’t matter if the training is physical exercise, advanced mathematics or just knowing how to act like the “right sort”, if you need it ahead of time jobs requiring it will pay more. It’s fair in a way, if still dysfunctional.
All the others are semi-skilled as well, except foreman which is a management position and so not usually included as unskilled. Chefs are not cooks, which is maybe more what you’re thinking of.