We used to think kids were like little adults, then we learned a bit about how the brain develops and how wildly wrong that mental model was.
But I was able to make some money by fixing computers or translating stuff from English to Czech anyway. There was no exploitation in those labor relations just because I was young.
I am not manually skilled, but I can definitely see someone at 15 making a nice chair or a table instead.
I don't think that 15 y.o.s should be treated as fully adult, some limitations on their work are perfectly OK (no ardous work, no work underground etc.). But barring them from working altogether will probably slow their development down. Not everything can be learnt from books or models, some real-world practice, including the most basic elements of interaction with customers/employers, is necessary.
I’ve met plenty of wickedly level-headed 15 year olds and a whole lot of irresponsible 30 year olds.
The variation is such to an extreme level too.
While teenagers are not fully adult in some ways, they are also very different from a 12 year old.
Until recently you could work once you left school. Now you cannot do a full time job until you are 18, but can become an apprentice (so you get some training as well as working). There is nothing to stop you doing nothing.
The requirement to not work until you are 18 has not been particularly beneficial. Brought to you (IIRC) by the same government that massively expanded the higher education system (a huge increase in the proportion of people going to university) for no real benefit.
