What was the artist trying to do?
Bergman here was trying to show how the fear of death is actually more destructive than Death.
How well did he do it?
He does it quite well, but having very different characters respond to the fear of dying (Skat becomes sniveling, the townspeople fluctuate from terror to sadism, Block see-saws from self-doubt to salvation and back again, etc) in different, all destructive ways. He also gives the family of Mia, Joff and Michael as a "control" example, a group unaffected by the fear of Death as they are too simple.
Was it worth doing?
In a historical context, definitely. At the time of the movie's release the Cold War was gripping all of the civilized world in fear, and there's definitely a parallel with the knight Block contesting against Death in T7S. In a contemporary sense the connection is a bit more tenuous (Cowie says that the same feelings apply to the fear of AIDS, but I really don't see the same level of fear between those two instances) but is still worthy of examination just in how it dissects the human condition, and in addition the meaning of life.