A lot of internal presentations and documents are never looked at or read; they're basically used as proof of work.
Like, I inherited a vibe-coded prototype recently, and writing about what the system does has been an invaluable tool in helping me (and others) understand the system.
And I think that nobody reading anything is much older than LLMs, it's just that LLMs have made it easier for people to produce longer, more irritating documents that nobody reads.