>>110011909This is a fine trope. It works in the context of clasisfying villains by whether they could be redeemed
by Steven or not, and generally getting the vibe of how seriously the story takes itself.
For example, Final Fantasy IV redeems the main antagonist, Golbez, extremely late into the game, by saying he was mind-controlled by the real main antagonist, Zemus, the entire time. This is a very questionable choice, but trying to analyze which one of them is a more "Complete Monster" helps put some difference between them and put Zemus(who doesn't get a lot of "screen time" due to being a twist villain)'s actions in perspective, making the contrived twist work at least somewhat by recognizing that Golbez is at least not the "Complete Monster" of the story. This is not kind of a situation that Moral Event Horizon is fit to describe, so I feel "Complete Monster" is more fitting for such dichotomy.