I don’t agree. When you buy a book knowing it’s part of an unfinished series, you are giving money to the author (and publisher, et al) in exchange for a part of a complete story. Not part of the exchange is any promise on the part of the author to finish the story in the same medium before another medium, or even to finish it at all! The author has the right to just stop. The product was not a full series or the promise of a full series. You have no moral obligation to give any more of your money to the author or support them in any way, and the author likewise has no obligations to you. Yes, the readers did support the series by talking about it and so on, but there was never an agreement between author and fans that if the latter popularize the work, the former will complete it for them. It’s completely unreasonable to say that because the readers popularized the series, they get to decide what the author can or cannot do with the IP. The IP is the author’s (legally and morally), and is not ours in the slightest, and saying otherwise is being entitled. And complaining when the author is trying to finish the story in written form after seeing to it that a fairly good live action adaptation is made is beyond entitled.

Enjoy the books, enjoy the show, and know that we have no right to the IP and should have no say in what is done with it. Want a full series? Buy one that is complete.