Yeah I think the future of what you describe is Chinese. They are already making autonomous electric tractors, but its early. Tractors are kind of uniquely suited to carry big heavy batteries and never get too far from the charging station. There are smaller autonomous vehicles that can do simple tasks like mow, and of course all the good drones are Chinese. I don't know if they'll make it open source, but they may not be openly hostile to users like western corporations. Deere and company won't just have a fee, all the telemetry, controls, everything will be tied into their own proprietary cloud shit, mandatory reliance on the dealer network, coupled with warranty service, etc.

Hopefully it's possible that even if a Chinese vehicle doesn't have FOSS software it's compatible with FOSS route planning software or diagnostics, or whatever. Maybe it's not FOSS out of the box but if you flash it, it won't brick itself because your binary isn't signed with their private key, or some shit. The lack of dealer would suck and of course, the government could just ban Chinese ag equipment when the check from Deere clears.