I have seen about five or six different reviews cautioning that “this isn’t your kids’ Harry Potter.”
No kidding! It has been billed from the start as adult fiction, why even mention that in the review? If your kids don’t read adult fiction normally, do not give this to them just because it is written by J.K. Rowling. Common sense. Reviewers, stop trying to use this angle to denigrate the book and evaluate it on its own merits rather than in relation to her previous body of work.