Except Jared and Holly are the villains and everyone else are the heroes.

I can only say why I think he's considered good but take this is as nothing but an opinion. Scott isn't outright malicious, he doesn't go out of his way to hurt anyone and when he does hurt people,it's mostly cause he's just clueless and socially awkward tries, he's considered good cause unlike most people who hurt others thoughtlessly, he learns and grows and understands why people got hurt by him and throughout the story, he goes through the same pain he put others through and comes out the other side as someone better who learned and suffered and does better because he knows the person he was, was someone he doesn't want to be.