The problem is automation and technology is getting so good that we don't need that many people working anymore. Autonomous vehicles have a very good shot of displacing a lot of jobs in a few decades. You can't also tell people in their 50s and 60s that you'll educate them for a new profession.

I remember an MIT economist Zhou Lin said this would be one of the big problems of our generation. I suspect Basic Income would have helped in the interim.