The narrator tells us that after the four pigs confess, the dogs "tore their throats out" (7.25), just as if he's saying the dogs went for a good run and peed on a tree. We're talking way, way objective—so objective that it has us worried about the narrator's mental health.
It's even more worrisome when we realize that the throat-tearing is a metaphorical way of describing how people were robbed of their voices by being forced to make false confessions—and then executed or exiled afterwards. How can Orwell possibly be neutral about that?
It's a good question. Orwell was one of the greatest essayists of his time. He could just as easily have written a tract denouncing the West's involvement with Stalin and the communist Russian state. Instead, he decided to write a neutral "Fairy Tale."
Here's what we think: Orwell's argument is actually more powerful because we don't hear the narrator saying, "Everyone sit down for your lecture." Instead, he teaches his lesson without us realizing that we're being taught—or, at least, we're in one of those modern, student-centered classrooms without someone wagging a finger in our face.