As for media, there are different mediums of media that allow for more trickery. For example, if a documentary says so-and-so did X, it would take some while after viewing the documentary to check if so-and-so really did X. You are putting faith with the people creating the documentary to tell you the truth. Whereas, good non-fiction books lay claims with sources to back the claims, so you can immediately go to the source to see if the claim is really true.
Also, video can be a very emotionally salient medium, thus may impede your more rational modes of thinking.
Note: I am not against documentaries, nor is this a take on the Khashoggi documentary.