When you understand that you need an uneducated workforce, then this makes complete sense.
Current US employment stats show two main chunks, HS+ and BA+, meaning the majority of the workforce is educated (and debited).
This gap was usually filled with migrants, educated or not, but cheap labour. Since that's gone in many Western countries, the dumbing down (and pricing out) of new labour entrants gives farmers and other blue collar employers access to a native labour pool of cheap, uneducated labour.
After all, whose going to work the farms, factories and mines?