Xi Jinping approves of this message.
Therefore, we are world filled with people who are dependent upon those who do understand these things and who can repair, maintain and do these things for them.
This way they can go about their busy lives doing their important things, while they depend upon other people to: cook for them, clean up after them, take care of their homes, yards and vehicles for them, educate and sometimes even raise their children for them, and take care of their retirements for them, too.
If you know how to do any of these things, then you are presented with a world of opportunities for life-long income and an undergraduate degree is not required.