And when the employers have to pay more for labor they will use their workers more efficiently including buying equipment to better utilize workers time. E.g., berries are picked more efficiently in New Zealand than in Califorania.
Second, UC Davis developed machines for picking every row crop and tree crop in California 40 years ago. The limiting factor is cost. But if/when wages go up, cost will no longer be a limiting factor. It'll all be mechanized. All of it.