Look, I'm not here to preach my belief in all living things being equal. It's something that should come from the heart. If you don't have it, you don't have it.
But like anyone I'm entitled to my opinion and in my opinion the scene is instant -2 to game rating. Why only -2? Because the quality of dialogue writing in D:OS is so poor and brain-hurting you have to be incredibly dim to take any of it seriously. Still, this particular remark coming from one of the game's more coherent characters (meant to be a good guy) and not triggering any response options from the player is insidious, one-sided and absolutely uncalled for.
And it's not even the only place in the game where such point of view is promoted. But hearing something like that from a dying madman is more of an "OK, whatever" thing. Here it really feels like a sudden punch in the guts.