Farmers don't want an open source tractor protocol for its own sake, but if it allows for greater flexibility, reduced costs, and improved serviceability, then

Farmers don't want an open source tractor protocol for its own sake, but if it allows for greater flexibility, reduced costs, and improved serviceability, then those will be relevant competitive advantages. You can see a similar phenomenon with linux on the desktop; Most people don't care about linux being open source in principle, but there is a meaningful, if small, amount of mainstream interest in it for reasons such as privacy and extending the lifespan of older hardware, both of which are enabled by linux's openness.