Very Few understand the Movie (SPOILER)
Only one critic of the several I read seem to understand the overall theme of this movie. Even critics I respect didn't get it.
These quotes from one critic capture it perfectly.
"The fatalism and mortality that pervade The Ballad of Buster Scruggs."
"The specter of death haunts this movie."
The theme is clearly defined in the first vignette.
In every vignette, at least one person dies. That's the theme. In the last one, the dead one is the body they've been carrying on the stagecoach.