However, it’s also uninteresting from the alternative perspective: if I made a famous novel series. In which case, I still believe what I currently believe, except now I am very rich, so thank you. I could—and would—submit the works into the public domain 20 years after their release and then live comfortably for the rest of my life.
Let me inform you of something: from 1997 to 2007, the HP series sold approximately 350 million copies. Between 2007 to 2018 it sold approximately 150 million additional copies. That rate will continue to go down, and Rowling would still profit off of the books because of what they’re already doing: expensive limited edition official releases, which makes superfans and other collectors go crazy and have high profit margins. Even if Rowling gave up the copyright in 2017 for the first book, she has the other books which would be in their own 20yr copyright term, and the trademarks which would be uniquely hers and desirable by consumers.
I would be very well off and nothing would really change, except now people can sell their own sequels/rewrites and make money too. Isn’t more artists having a chance to make a living a good thing? Or only specific artists? If someone rewrote the series but if Malfoy was a girl and in love with Harry (à la the recent Malfoid memes) shouldn’t they be rewarded for their work if the market deems it high quality?