The Human Comedy belongs in that sub-genre of sappy WWII propaganda films like The Best Years of Our Lives, Hail the Conquering Hero, and Mrs. Miniver. Unfortunately, it's much worse than any of those just mentioned.
No doubt, if it was 1943 and I had just lost a loved one to WWII, I would be more in tune with the bittersweet mood of this movie. That being said, it's still terrible. The world in this film is so ridiculously wholesome that it could be (and maybe is) one of the inspirations for Pleasantville. I forced myself to sit through every painstaking minute, because it won an Oscar for best screenplay. I suspect that it really won the Oscar for being a WWII movie in 1943.