If the original author chooses to do that, fine.
The Fall of Reach (a fan favorite and one of my own favorite novels, incidentally; I still have my childhood paperback in which my mother pencilled my name) is a licensed novel in the
Halo franchise. The decision to create the revised editions was made by the company who contracted Eric Nylund to write it a decade before. They didn't make any thematic changes, just technical ones, but legally, they could have issued a far more substantial revision, as the Stratemeyer Syndicate did with some of the
Hardy Boys novels.
From 1959 to 1973, Edward Stratemeyer's daughter Harriet Adams oversaw a modernization of the first 38 books, removing references to "roadsters" and "automats" and other terms considered dated, excising some racial stereotypes, "streamlining" the language (sometimes at the cost of "humor, charm, or believability"), increasing regard for police, making Aunt Gertrude less cantankerous, and cutting the length from 225 to 180 pages. There were
four levels of revision ranging from minor edits to the complete replacement of the entire story except for the title:
1) Same story, same text: most of the original text remains intact, with pieces cut or slightly altered here and there (example: The Phantom Freighter
).
2) Same story, new text: the basic framework of the plot is the same, but the text has been completely (or almost completely) rewritten (example: The Tower Treasure
).
3) New story, old ideas: the book has been completely rewritten, and the plot is not the same, but some elements are retained, such as names, capers, episodes, or locations. (Examples: The Twisted Claw
retains many elements, such as the Parrot freighters, the pirate empire, and the Caribbean island. The Sinister Signpost
retains the racehorse named Topnotch and Aunt Gertrude's inheritance of a stable of racehorses, but their relevance to the story is completely changed.)
4) Completely new story: the book has been completely rewritten and shares no elements with its predecessor (example: The Flickering Torch Mystery)
.
The revised editions contain no mention of the originals, and very few people who have read the "original"
Hardy Boys novels in the past half century are aware of the true originals' existence, which I think is unfortunate; I'd prefer to see revisions always noted.
If someone dumps it all into an AI program and tells it to churn out a uniform continuity by mindless algorithms, that is garbage and theft and a betrayal of every author whose work is abused that way. Consent makes all the difference.
An official revision can be garbage, like George Lucas' bad CGI additions to his original trilogy, and an unofficial revision can be excellent, like
The Phantom Edit, which was praised by Kevin Smith,
Salon, The Chicago Tribune, and many others as a masterful improvement upon the original. Or, the
Extended Mall Hours cut of
Dawn of the Dead which combines all unique footage from the three official cuts to create the longest possible experience; this cut became so legendary that it was eventually recreated as an officially licensed cut (but without director George A. Romero's permission since he could not be contacted from beyond the grave). That these were made without the original filmmakers' consent is immaterial to the fact that they are transformative works which many prefer over their originals.
This goes back to Shakespeare's unlicensed reworking of Arthur Brooke's
Romeus and Juliet into
Romeo and Juliet and long, long before.
This thinking is the end result of modern fandom's unhealthy obsession with continuity as the single overarching priority in fiction.
I certainly don't consider it the "single overarching priority," but there's a world of difference between substantial alternate continuities such as the Rihannsuverse and stories which can fit together perfectly except for a few extremely minor discrepancies in dating which can be harmonized without changing the narrative at all (or, again, correcting objective internal inconsistencies within a single text).
The purpose of telling stories is not to "fit together" or "get it right." It's to exercise the imagination, to explore possibilities. Continuity between stories is an option that authors can choose to employ or not by their own free choice. If you start to think of continuity as something that needs to be mandated or imposed uniformly, then you have completely lost your way.
It's really both. Some amount of continuity is mandated in licensed fiction, and no series can sustain itself without some continuity...
Only the authors and editors should have the right to modify their work. Anything imposed on it without their consent is an assault.
In the case of licensed works, this right often belongs to the license holder, and in the case of public domain works (where all works eventually end up), this right belongs to everyone. Furthermore, some unofficial revisions of works still in copyright are protected under fair use as transformative works. There's also no law against crossing out passages one doesn't like, writing in the margins, or using whiteout to insert new lines in a copy of a book one owns, nor deleting and adding bits in an ebook for personal consumption.
Ultimately, we'll reach a point at which any novel can be instantly adapted into a holonovel à la "Qpid."