Yeah, it's not that they criticize the actual problems with the texts, or, more importantly, the wider social problems that the texts reflect. Instead they reinforce some of the messages of the text in their own behavior - women are stupid, women's choices don't need to be listened to, men know better and are allowed to treat women with contempt (I'm generalizing on genders here because I, personally, have only seen young men policing young women over fan-status IRL, though I'm aware that women also police other women as well).
As for its appeal, I think Dana over at RwV made an excellent point about the dangerous irresponsibility of writing the protagonist in a way that normalized and even romanticized self-loathing and self-destructive tendencies. Would I have liked the books if they came out when I was 17? TW
Probably, at that age I was a dazed little ball of self-loathing constantly prone to self injury and suicidal ideation who was in an abusive relationship
- I certainly would have been able to
identify with the protagonist, even if I disliked her and her decisions. Reading about her self-loathing would have been like irresistible literary crack.
Also, I was up until 3:45 am reading the entire archives of RwV, because they were awesome. Thanks, Hex

Edited to remove some unnecessary detail from the spoilered section