The characters were so well done I actually felt dislike towards the "bad" ones. That's not a common thing for me, since I rarely feel real negative emotion towards "bad people" in fiction. I usually just think "oh this is a bad person", and enjoy what they bring to the story. Sometimes I might even like them, despite knowing what they do is wrong.
But, that definitely speaks to how well this story portrays people. It feels so real it becomes hard to bear. I never personally experienced bullying to the level this movie portrays, but I did experience enough for this to feel frustratingly real. Even non-bullying parts where it's just someone who refuses to take accountability and lies through their teeth get me riled up. As someone who's true to myself and honest to a fault, I've always disliked dishonest people. I can very much understand why they might be that way, but I think anyone would agree with me if I said I would much prefer if they could just... "be real". Or at least tried.
To be honest, that's kinda why I didn't give this a 10, even though it honestly deserves it. Basically, I don't watch entertainment to get pissed off. But, still, I can say I absolutely see the value in media that can do that. It's just not necessarily for me specifically.
If I were to just rate it based on how well I think they executed what they set out to do, it would probably have been a god damn 11/10.