Some thoughts:

“”” America has run this experiment before. In 1964 about half a million Mexican farmworkers were shut out. In 1965, 20% of California's tomatoes were picked by machine; by 1970 the figure was 99.9%.“””

I honestly had not considered closing down (legal) immigration as a forcing function for automation. Industrial policy as immigration law.

But I don’t think I get the rest …

Higher costs onshore mean machines give us an advantage - i get that. The rest I may be missing