I was referencing the one you were implicitly defending that started this line of chatter:
https://www.ala.org/bbooks/frequentlychallengedbooks/top10 Most of the books from that list are widely available and easily accessible. The 'under threat' rhetoric is just from them being removed from some schools due to content being deemed age inappropriate. Those pg13 movies with nudity tend to be things like a few seconds of sideboob in a shower or whatever.
The top book on that 'challenged' list is a diary style book of a 13 year old girl who is sold into sex slavery, repeatedly raped, abused, and so on - with descriptions of each 'encounter.' The book is meant to be, and indeed is, extremely disturbing as it's part of the author's activism against sex trafficking throughout the world - as it was based on real events as per her research. In any case, it most certainly is not PG13 by any stretch of the imagination. It's much closer to something like Requiem for a Dream than it is to Tomb Raider.
I also think that's a great book to have on top, because it emphasizes that the issue isn't ideological, but content. I think there's few people who would claim Sold doesn't have tremendous value, or that it should be banned. But there's going to be a lot of people that don't want books like that anywhere near children. And for good reason - it's the same reason I wouldn't really care if my kids wanted to watch Total Recall or Terminator, but no way would I let them watch Requiem for a Dream. The violence and triple titted aliens of Total Recall are borderline comical, but I don't think stuff that gives you that awful 'ughhhh' feeling like Requiem for a Dream (or indeed - Sold) is something that's going to be at all healthy for a child's development.