It is a media franchise for children, and there are many elements, and trademarks in addition to copyrights. I think most fans understand the bright line that stops them copying an entire book or film work, unless their dad has a Roku at home.

But there are over 34,000 images uploaded to the Fandom.com site alone. There are character bios and generous quotes from films and books. Countless fans are using elements in memes and avatars and social media posts.

Fan-fiction abounds, where the characters and scenarios are endlessly remixed and mashed up with other fandoms.

Quidditch... simulated... is a collegiate sport, but they had to rename it.

Even on the official Wizarding World site, you can make custom downloadable stuff. Not long ago, freely download wallpapers. Get free clips and trailers on any video site.

News outlets had a difficult time explaining the "Public Domain" status of Mickey Mouse and Betty Boop with the new years. Because Mickey Mouse and Betty Boop, the characters, aren't the things which are copyrighted, and the characters' status didn't change with the new year.

I would bet that the typefaces in the official books have their own copyrights, and the book binding processes are patented.