Ways of Thinking about Endings

I think what the article's author means by abrupt ending is the narrative. Did the story's ending come to a complete end, by which I mean: did the expectations of the reader setup by the narrative become fulfilled by the very same narrative? Have you ever read a work of writing and wanted more? Now, there's some nuance here. You could be feeling as a reader that surely that isn't all there is in an incredulous fashion; or, you could be itching for more from your chosen work because you want, no, need more from this author. Certainly, this will vary from reader to reader and much of this is an art of sorts, but good writers will practice their craft often enough that they'll know what the readers want and choose whether and how to give it to them. I think in many ways when the author must invoke some element of writing such as a character or description of background that always by necessity an expectation is being setup for the reader via tropes or genre or curiosity or what-have-you to be met, subverted, or unmet as necessary or by accident depending on the author's skillet.

I think in the examples you cite that the context of when the story was written and the collective opinions of critics and readers will form a sort of cultural sediment or milieu which inform subsequent readers. The weight of these informed expectations can buildup or bury a work for various future or subsequent readers. Stephenson might be criticized for an ending which may, rightfully or wrongly, lack a sequel or a resolution to the action or various plot threads. Some people will read Neal's more famous works as standalone novels or classics without knowing they have sequels. We might get open ended finales such as the merger of Wintermute in Neuromancer and the bittersweet farewell with Molly without knowing the consequences of the narrative. What happened to Molly? What will the AI do now? Why does the AI merger matter so much? I suppose one could take these as unresolved plot threads. I certainly enjoyed the books, but it's been decades at this point for me. I'm always surprised how well Stephenson's work holds up for me over the years.

I am reminded of Hemingway's entry in a six word short story competition: "For sale, baby shoes, never worn".