> As I said, when farming became more efficient, it wasn't great to be a farmer
What you seem to be saying is that consolidation of the farming industry into fewer producers with higher productivity was good for food buyers and society at large, which might be true but doesn't contradict GP's point that when their company earns $100 more due to improved employee productivity, approximately $0 of that will be paid to the employees, so they find little reason to celebrate.
The link I posted makes somewhat different yet important points: first, the arc of automation seems to tend toward increased inequality (and a hollowing-out of the middle class); second, automation may provide a markedly worse (but cheaper) replacement for the thing it replaces. Even in the case of farming, many fruits and vegetables are less nutritious than they were 100 years ago - perhaps effects of selective breeding (such as for size, shelf-life/durability, resistance to pests/pesticides/herbicides/etc.), soil depletion, environmental changes, etc.