There have been many altered Bibles published over the years, from just modernizing the language to more extreme changes like the Jefferson Bible.
But the one thing all of those versions do is make it very clear that they're altered versions. Even the one that many people think of as THE Bible is such an altered version and is clearly labelled as such: The King James version.
This one remarks there are a half-million variants of the New Testament. It does not seem to be in doubt that there are at least tens of thousands.
https://equip.sbts.edu/article/can-really-trust-bible-manusc...
There seems to be an academic field that studies them, how they evolve and split like an evolutionary tree. The way things are going, by the end of my life that field will have to expand to all literature.
And personal versions like the Jefferson one can be discounted - that's not the subject of the conversation. Anyone can change a Dahl book, but we're talking about all the big publishers changing it.
Certainly not all, but that's not really relevant to the discussion of whether or not it's OK to change an author's work and represent it as the original.
> What if all the publishers did a wholesale slaughter of the "holy" books
Well, that's just an extreme and paranoid hypothetical and is unrelated to what we're actually talking about here.
> nobody could get a King James that didn't have significant changes
If there are significant changes, it's not the King James version. Calling it that would be wrong.