It seems like it won't be a popular opinion given the comments, but: a three-letter-agency, especially the CIA, maintaining a "factbook" always seemed like an oxymoron to me. Indeed it was an oft-cited source in research and school essays, and for the most part it was certainly accurate, but, as many tools of propaganda, that veneer of accuracy could be a useful cover for the small portions of reality where truth was inconvenient.

As an example in recent memory: the World Factbook has been heavily cited lately to argue against the idea of a genocide in Gaza. Maybe a year or so ago, the Factbook was updated, and it claimed that the population in Gaza had grown: no decrease, no inflection point in growth, nothing to see... That claim was in heavy rotation, as soon as it was published.

That the espionage agency of the main weapons supplier to Israel would publish such a claim felt grotesque, and the claim itself seemed ridiculous, impossible, based on even evidenced peripheral information (the 90+% of people displaced, the destruction of all hospitals, the deaths of so many aid workers, the levels of starvation), but... the Factbook claimed it, so it became true to many.

It would be impossible to quantify the effect of this, how many days of horror it added, how many more debates those trying to stop the killing had to do, how much fewer donations were sent to aid workers. But an effect it certainly had.