More hyperbolic than facetious. It can’t be a good thing to disenfranchise the holders of your strategic resources en masse, and farmland was the easiest to point at.
You’re right that it’s extremely unlikely to get so bad that they get forcibly nationalized. However, my understanding is that market conditions are pretty bad for farmers right now, and have been for years. Any change that makes things worse for them will likely drive some to other lines of work and reduce overall production, driving food prices up.
This particular effect is probably extremely small in practice, but I felt the need to remind HN that not all value is produced in cities.