Drivers rarely owned the medallion. They leased the cab for 8-12 hours and drove it on behalf of the medallion owner.
You will be glad to learn that most farmland is farmer owned:
https://www.ers.usda.gov/topics/farm-economy/land-use-land-v...
The USDA is not trying to pull a fast one with the definition of a farmer.
We could have a discussion about farmers that have other jobs and so are part time farming and part time something else. That tends to correlate with less intensive farming like corn and soybeans.