I agree that our system relies heavily on uneducated migrants for menial labor.
However, uneducated people in the 1950s regularly got jobs in factories that paid enough for a single income to support a family.
That opportunity for uneducated Americans won't come back, regardless of our immigration policies.
It’s likely that automation is about to turn the world on its ear vis-a-vis low skilled employment. The cost of human sustenance and care is surprisingly high compared to electricity, steel, carbon fiber, and silicon.
While it's true that it was possible to support a family on a single unskilled laborer income in the '50s, their standard of living was far below anything most people would accept today.