Hiring Convicts and Morons

I'm reading a fascinating book from 1921 on "Personnel Relations." It's a 200+ page manual or perhaps textbook applying "scientific principles" to the personnel industry.

In a chapter on Interviewing, it talks about how every adult should be capable of being hired and the focus should be on finding the proper "adjustment" between the worker and his job. The text literally states that the only reason to reject an applicant would be if the worker would be injured by the job or would injure his fellow-employees and/or society.

It goes on to say,

"Establishments that a few years ago were hiring a small percentage of applicants and yet had a turnover of 400 and 500 percent now boast of their ability to use such exceptional classes as discharged convicts, morons, disabled soldiers, and industrial cripples, with a lower turnover and improved production."

Work really has changed over the years, hasn't it? In the 1920s there was evidently and unlimited number of unskilled jobs that needed to be filled. For "personnel professionals" of the day to be even suggesting that there was a job for every person who applied is incredible.

Wouldn't it be nice if in today's world that the job openings across the globe were exactly equal in number and requirements to the skills and qualities of all the people who are unemployed and job seeking?