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?
Yes but not every job requires years of training and certifications. Skilled labor jobs are those that require years of training and certifications eg plumbers, machinists, doctors, lawyers et al.
It isn’t class warfare to suggest the guy whose job is to empty trash bins is doing unskilled labor as most can do that job.