I think it depends on when you cut relative to the fawns being born. All the ones we have hit have been at the “mama leaves me alone all day” stage.Don't know anyone that has hit one with either. I know a lot of people that operate tractors.
You gotta look at the herd as a whole unit as opposed to individual deer. We have hit and killed a few fawns during our day as we were managing our land. But managing land typically makes it better for deer overall so sometimes a few are going to be sacrifice for the betterment of the unit. Sad but true.