The movie makers managed to tell a story without telling the story.
A story about a scientist who builds a bomb knowing well of it's destructive properties and the fact that it will be used to kill thousands of innocent people is shown in a good light?? And people fell for it? They showed him as troubled, complicated and sad!
To quote the movie "You don't get to commit the sin and then make us feel bad for you that it had consequences" Oppenheimer built the bomb that not only killed thousands of innocent people, it cursed the land and the generations to come. The fact movie makers conveniently forgot to mention.
Every now and then he feels guilty and sad, are we supposed to shed tears for him?