I think the whole 'flat earth' theory is a very clever 'poison the well' tactic of NASA. People are figuring out that the moon landings were fake and are questioning NASA, and now suddenly there are people saying that NASA is lying about the earth being round. This conflates the two (poisoning the well), and makes it that if you doubt NASA you are mixed in with flat earthers.

Example: "Oh, you don't believe in moon landings? What are you, one of those flat earthers?"