It's an interesting commentary on the film audience that it's so easy to see Batty as just a villain who had a moment of weakness. That interpretation is not consistent with an unbiased viewing.
If the film had been shot from the perspective of the replicants instead of Deckard, then it's a story of a cruel government hunting down escaped slaves like animals. The narration implies that we shouldn't take a broader perspective, we need to watch the film good and biased. Accept the cinematic manipulation and the establishment line.
Exactly my reaction. The narration heavy-handedly pushed us to interpret the ending in a particular way. Once I saw the film without the narration and was free to decide for myself, I understood the ending in an entirely different way, a way that had far more meaning and impact.