I think everyone here knows I'm a social science researcher and one of the things I work on is the communication of science. This single thread just substantiated several things I've been arguing about with some folks for a couple months so thank you all. I made an ethical vow to never use this forum for research, but it's definitely useful ammunition for demonstrating to colleagues how off base they are about what attracts people to certain information. What most people who study rumors and conspiracies agree on is that they have to be assessed independent of a value judgment on the contents to try to get at what they do for people, whether it's helping them to make sense of things they're alienated from or allowing them to mobilize to challenge established authorities. Several people I know seem to falsely believe that it's a literacy or even intrinsic issue, but to me either explanation gives people less agency.
Something I'll say about flat earth theory is that gravity and relativity don't work the way we understand them at the planetary scale on a non-spherical object. Ergo, no such thing as satellites, no such thing as space shuttles or space stations and certainly no such thing as the Mars rover. We can plainly see the moon line of sight and it too wouldn't have a spherical shape (considering its size and distance) if earth didn't. Also Kron has been to Japan and must have obviously noted he was a day in the future.
So any hypothesis about a flat earth would also have to account for the existence of all of those things, to say nothing of the improbability of an entire planet's worth of governments who often hate each other who would have to collaborate to suppress the truth. But I don't believe anyone cares to do all of that work because claiming "the earth is flat" doesn't mean you literally know or care. It usually means, as
@Masato Toys eloquently put it, that there's a deficit of trust somewhere else.