You have to understand Farmers.
It's not about right to repair. They are perfectly capable of repairing their equipment. And no one is forcing them to buy John Deere. There are a LOT of OEM's out there in all sectors to choose from. If they don't like the black box that's running their equipment, there's nothing stopping them from buying a blank controller and programming it themselves.
It's about them wanting to circumvent systems. Whether they are safety systems to prevent injury, safety systems to prevent excessive damage to the machine, or regulatorily systems for emissions.
Famers want to bypass that shit constantly.
They want to put cheap shit diesel into their engine and who gives a shit about the environment.
They want to run their machine at 120% constantly. And then bitch to the OEM their machine broke too soon and wants warranty.
They don't want to wear a seatbelt, or have a seat switch in their cab, or a spring return propel joystick. They want to rig up a bungy cord to the throttle and get out of their seat to go look at something while it drives.
Farmers weld up some of the STUPIDEST and most dangerous contraptions that I've ever seen with absolutely no education/calculations as far as frame weight/load or torque requirements/etc. "My Daddy did it back in his day, so I should do it too!!!"
And yet we get farm accidents/injuries constantly, including CHILDREN. And yet none of them are ever charged or imprisoned with running an un-safe environment/operation like any other industry would. You can't have a 14-year old driving around a forklift in a factory without getting into serious trouble, but sure let them run a combine or tractor.
Farmers wanting access to source code is 100% because they want to disable shit.
It has nothing to do with repair, it has nothing to do with adding 3rd party shit. You can already do that. I do that on a daily basis for a huge list of OEM's both in and out of the ag industry.
They already have the right to repair. Nothing is stopping them. The only thing stopping them is that you need a little more knowledge these days than basic mechanics and some welding skill.
If someone doesn't like John Deere. Stop buying fucking John Deere. You want to have full control of your machine? Grab a mobile controller and have at it. No one is stopping you.
There's nothing special about John Deere. 90% of their shit is standard J1939 protocol, and the few proprietary messaging that is John Deere specific is available if you ask, or you can sniff it out easily.
All locked down maintenance stuff is 100% there to record and verify that the farmer is taking care of the equipment properly.
The amount of "I want warranty!!!!" bitching, but they didn't change any filters, abused the machine, or used it for something it wasn't designed for is far worse than any car mechanic shop you've ever seen.
It's a free open market.
If you lose your power, just switch to another supplier that doesn't go down.
EDIT: HAHA didn't know I had to put a obvious /s on this comment, but there ya go.