Comment by Aachen

> Then millions of people use the output uncritically.

Or critically, but it's still an input or viewpoint to consider

Research shows that if you come across something often enough, you're going to be biased towards it even if the message literally says that the information you just saw is false. I'm not sure which study that was exactly but this seems to be at least related: https://en.wikipedia.org/wiki/Illusory_truth_effect