> 4. It seems to assume the reader has a lot of context that isn't explicitly laid out (and which the reader wouldn't get just from reading the prior work, which is cited

I've had this complaint well before LLMs were used. People writing about topics they have a lot of knowledge in the subject tend to make the assumption only other subject knowledgeable readers will read it. Or that it never edited by a real editor that would enforce rules like spelling out acronyms on first use. Or forcing additional information when too many details have been left out on the assumption it would already be known.

There's plenty of this type of writing to have trained the bots that way