Halloween // Is Harry Potter costumes still acceptable?

Im not sure if this is the right subreddit to ask, Im sorry if it's not! My cousin wants to be a Harry Potter student this year but Im not sure if it's still okay to dress up as one due to the authors views and how she's a pretty bad person. So I guess my question is if it's still okay to dress up as one or if I should tell my cousin to dress up as something else! Any advice for other costume ideas and in general is very much appreciated!!