Yes, they're engines that you wouldn't be allowed to build and put in a new tractor.
Like, the signals seem pretty clear to me. The spirit of the regulations is that these shouldn't be produced and put into operation anymore. The company is doing it anyway.
You're right about the emissions dimension and that there are good reasons for reducing pollution, even if the company isn't putting new engines into use but only elongating the operation of existing ones. On the other hand the right to repair and dependability angle is real. There are problems that need to be solved and they need to be actually solved. If they aren't a bunch of us start to starve and get angry. It doesn't go well.