There is quite a lot of good advice here, however with one caveat. Documents require constant maintenance, and a "living" document that several people can edit is probably contradictory to the "always stay accurate" principle. Not everyone shares the same mental model of the project and sometimes things change but not everyone knows at once.
You can choose an accurate document that doesn't change often, or an accurate-ish "dynamic" document that is managed by a single entity, or a document editable by more people. You can't have a perfectly accurate document that's also changing constantly and is managed by multiple parties.
As a side note, thank you for not coming up with silly acronyms for everything.
Having multiple "opinions" or "views" on a certain thing,can make you "see the average" and get a very accurate representation of the situation. Yes i agree that most of the times there are people messing around and can "hurt" that average, but on the other side it is another perspective on the situation.
Having a constant flow of these data can make a pretty accurate "end-product" document.
you manage the consistency of the "artefacts", at a sufficiently fine granularity, using anchors and pointers and some semantic versioning of each, so you can contain rippling effects (fix a typo vs just add sth vs overhaul a part).
and in that tracking you also capture the "known deviations", like 'this need isn't fulfilled yet, at all'. thus you document the "state of the union" of the whole thing, which for a living collaborative work is all you can wish for.
This is the idea behind "requirements management" and "requirements tracing". Alas, there are few tools out there doing this with a low barrier to entry, cli like.
You can choose an accurate document that doesn't change often, or an accurate-ish "dynamic" document that is managed by a single entity, or a document editable by more people. You can't have a perfectly accurate document that's also changing constantly and is managed by multiple parties.
As a side note, thank you for not coming up with silly acronyms for everything.