Ask HN: Is documentation a solved problem or are we all just pretending?

Every company I've worked at has a Confluence or Notion that's 60% outdated. Decisions happen in Slack threads and Zoom calls and never make it anywhere permanent. New people onboard into a fiction. We have AI that can write code, generate images, and pass the bar exam. But somehow "keep a document up to date" is still unsolved. Am I wrong? Has anyone actually cracked this?