> Typically whenever a once competitive firm becomes a lazy monopolist, at some point others want to break in and get a piece of the profit pie. It could happen someday.
The problem is, as in many other domains, a combination of opportunity cost and network effect.
Getting in the commercial farming game is going to be expensive as hell and gruelling as you try to get a foothold, and unlike, say, a car, your average farmer has a ton of equipment from the same brand which works together, and the more time passes the harder it becomes to interop (though I guess at least in farming you don't have too many patented hitches or PTOs these days?)
Not to mention in farming you really need to have a network on the ball for parts and repairs, if you fuck up a farmer's season by leaving them stranded for a week they're not going to be happy campers.