There won’t be any “farm workers” for planting, cultivating or harvesting crops in another 15 years. As a John Deere guy told me, they can put in a crop of corn without a farmer being involved other than to initiate actions. The reason farmers still drive tractors is because farmers like to drive tractors. But where the tractor goes and what it does is all automated. See “Precision Agriculture”.
Yes, the tech to farm without farmers is getting scary good. But, equipment maintenence takes people, and machinery breaks, gets stuck in mud, has to switch implements (hook/unhook hyd hoses/electric cables). So, terminator will have to be good enough to do those chores.
Crop duster pilots are probably wondering when drones will be doing their jobs.