I never dislike Hermione, but on my first read around she came across as the smart girl who was SUPER defensive about it because that was like... her defining thing. If she wasn't the Smart One, who was she (is the vibe I got from her).

Now, that could just be the writing, and it never excuses the way Snape treated her, but I don't remember anyone else being cruel to her because she was smart? I mean, Umbridge was a bitch to everyone, so I don't think that counts.