Reasons

1. Farm Simulator has reasonably realistic vehicle dynamics and appearance.
2. It has a thriving modding community (though, as I came to discover, this is despite the terrible API documentation that's just a doxygen dump).
3. in particular, the FS19 version of the flagship Courseplay (Archived) on-field automation mod (see also autodrive (Archived) for road networks) hasn't had a commit for since Christmas Eve 2021, so I bought FS22 on sale. It does seem less buggy.

So, I'm going to try using it instead of the more recalcitrant GTAV as a simulation platform.

I spent some time setting up a development environment and some scripts to quickly reload script changes.