I have read it. Genuinely, I’m trying to understand what you are establishing as the legal relationship between an employee’s actual productivity relative to their paycheck. Just seems like the specific use of the word “illegal” does not compute in the context at all. “Irresponsible” or “fiscally wreckless” seem like more applicable terms.
That’s without even getting into the can of worms that “value” from an employee is highly subjective, and dependent on multiple variables even for menial jobs, anyway. Therefore its almost impossible to ascertain to any degree of certainty. Punctuality, reliability, flexibility, communication skills, along with of course general output all go into what makes one valuable or not so valuable, to a varying extent for each depending on any given job or position.
“it makes it illegal for them to work unless somebody hires them as charity or by mistake.”
Option 1: they illegally pay them a wage that makes sense.
Option 2: they pay them more than they’re worth out of a sense of charity.
Option 3: they pay them more than they’re worth because the employer doesn’t realize they are doing it (I.e. because they are making a mistake)
If you wanted to go for extra credit and read past the part you bolded, I acknowledged the Possibility that an employer was paying them because they thought they’d learn to be worth more in the future, but I’d argue that’s just a special case of them being worth more than their wages or alternatively, of the employer making a mistake if the employee doesn’t stick around long enough to let the employer recover its investment in the employee.
There may be some other explanations of why a employer would choose to lose money in an employee, but regardless, it’s a bad idea and I would argue immoral to make it illegal if an employer to pay an economic wage to a low skill employee unless the employee meets some minimum productivity threshold.