I’m not sure where this idea came from that farming was idle and only industry required constant work. Every hundred-year old book I’ve ever read that features farming includes themes of how the farmer’s work never ends and runs from dawn to dusk.
I've worked on a traditional farm, and it's definitely hard work, and lots of it, but it is finite. Sure, there are some things you could always do, but usually there are a fixed number of tasks you plan for a day, and many of them have to be done at specific points in time. This naturally creates breaks between work.
There's a lot to do on a farm, yet no farmer is expected to be working a full 8 hours a day, 40 hours a week, at moderate intensity. No farmer has to do something within the next hour or their boss shouts at them. No farmer has to feel bad, or need to catch up, if they have to take a day off unless it's planting season. No farmer has any qualm about ending a day early because they've done all they planned to do. No farmer obsesses with stimulant medication or correct dosage of modafinil to get through their daily work.
And there's a huge difference between a subsistence farmer, which most of humanity has been for most of history, and intensive farming, which admittedly benefits from machines, but it's anyway a much more regimented industrial operation.