I specifically said that I liked where he ended in Volume 7, I hated how Volume 8 handled it. What Ironwood actually did wrong was neglect Mantle, taking shit from them, enforcing curfews instead of updating security not fixing the wall, the whole ‘unlicensed huntsmen’ bit in Episode 1, and then when push came to shove leave a good chunk of the population to fend for themselves.
Ironwood certainly tried his best in V7. But he also had a tragic flaw, and that was being self-sacrificing in a way that was almost insistent on him being a hero. A sort of, “I love you, and that’s why I must do THIS for you, and I know THIS is good because it requires me sacrificing something, so you should be grateful.” thing.
Think of it as a dad who keeps toiling away at giving you that baked casserole that you don’t really want, because you are his child, and so he puts in that work out of parental love, yes, but also out of a need to be your provider. So when you don’t want the casserole, a resentment builds up. This sort of thing is subtle, but it’s believable, and is actually a really complex sort of flaw also tied to Ironwood’s good qualities.
But what makes Ironwood a good character is how his story is almost completely tied to the main conflict of Oz V Salem. You don’t really get Ironwood without Salem vs Oz. Ironwood wouldn’t be acting in the way he is if it weren’t for his knowledge of her (and how it evolves) and the events of Beacon. He is one of the only characters to have active opinions about the salem vs. oz war and go their own way.
The outcome of that story has huge repercussions on him as a character. But you can’t say this about rwbyjnr, who act more like bystanders that throw wrenches in the plans of the major players (Ironwood, Oz, Salem) by chasing macguffins and sometimes stumbling into character arcs along the way. You can get them all as virtually the same characters even if the Main Plot turned out to be something entirely different; the same is not true for Ironwood.
He’s also a great villain because it feels like he really does fit in the world of rwby specifically. With the grimm and Salem, it makes sense that quite a few people that think like him would exist. Grimm being attracted to negativity means that “negativity” per say is something that differs in amount means some measure, you can simply judge things based on how many anti-hedons they produce. No need for “philosophical nonsense” like equality or some such; the world has already answered these questions for you. A valid extension of this line of thinking is that throwing Mantle in the trash is perfectly justified if the negativity produced by the people of Mantle doesn’t outweigh the negativity produced as a result of Salem’s plan succeeding... which... surprise! Is the conclusion Ironwood comes to.