- Why did everyone start to hate the Russians if the U.S. did the same thing in Afghanistan, Iraq?
- What needs to be corrected in the management of Russia first?
- Why did Blaise Pascal become a religious man at the end of his life?
- How do I know if a guy likes you?
- When they say "one generation", how many do they mean?
Of course, this is a very rough and general judgment, but there is still a grain of truth in it, and I think the reason is that mostly physical labor is now mechanized. All machines are created with the help of mental labor in the first place. A machine can not have intelligence (at least not yet such a system has not been developed), so the intellectual resource becomes more and more valuable. In addition, there are some areas that the machine will not be able to repeat – writing a picture, book, or poem. Yes, you can program a machine to do this, but still the end result will not be the same as a human will make it.
Appreciated by whom? In what way is it valued? A locksmith can earn more than, for example, a teacher. But the locksmith does not perform quite mental work.
If we talk about the attitude of society to mental work (and, apparently, this is exactly what you meant by “valued”), then mental work implies the presence of some intellectual abilities, requires more mental resources, and training in it is more difficult than training in the same locksmith business.