I need to assume that you're basically accusing it of doing a Goblin Slayer, and I likewise need to insist that this is a very lazy reading. It is made very explicit that being a demon is basically a transmissible human health condition caused by medical experimentation. No one has been or seemingly could be born a demon (the only apparent exception are those sub-sentient fish creatures the jar demon spawns, but they also might just be an extension of him since demons are many times shown to have these sorts of connections to each other or separate parts of themselves), they weren't born out of anything but humanity, and the condition can even be reversed medically, though that discovery is of course late-coming. On top of all that, it is readily shown that demons can be good people who don't do murder, and indeed ~4 are shown to choose not murdering, it's just that the people Muzan picks out are ones who are more likely to give in to the desire to eat people. There are many things separating this conceptually from some sicko racial allegory like Goblin Slayer is.