[KedarMhaswade]

The essence of the article is about effectiveness of technology/trade in reducing the 'gaps' between the capabilities of workers/artisans results in lowering their average compensation. But I think there's something missing. Professor Katz famously suggested not to become scientists [1] because getting your research funded becomes top priority than the assurance that 'all you'll do is research'. In a way, since we live in a society, workers need to feel personally responsible for /constantly/ finding the appropriateness (value) of their skills and elevate them as necessary to make sure they have a steady income and their craft is still valued by 'customers'. If you stagnate there, then you will gradually (or rapidly) become replaceable. And as you age, being indispensable becomes harder. So, perhaps, it makes sense to learn things that ensure stability of demand for your skills.

1- http://physics.wustl.edu/katz/scientist.html