While not a flat earther, I gotta bring some balance here
'Encyclopedias' were/are wonderful but again I don't think its wise to give them all-trusting authority on reality. There is an interesting history of the Encyclopedia Britannica being bought up and managed by the Rockefellers. The original publishers put out 9 issues, then Rockefellers bought it and started running it at the turn of the century.
This is the 9th edition, before being bought up:
This is the next edition (curiously they skipped 10 and went straight to 11 for reasons I will not speculate on here, lol) Note the 'inc' at the bottom:
But seriously; an encyclopedia, claiming the authority on all facts about our reality, run by Rockefellers/Standard Oil, who had also bought out/were shaping the medical industry in their likeness, bribing politicians left and right, and even involved in wars and world politics etc etc etc? It seems ripe to me that the temptation to edit these encyclopedias very carefully in their favor on a number of topics would be too valuable to ignore. The ability to use this to steer entire generations of people towards their purely allopathic, capitalistic, atheistic, anglo-centered, consumerist goals imo is monstrous, and likely.
Flat earthers are for sure at the extreme and of keeping one's head in the sand, but IMHO so are those on the other end of the extreme who trust Encyclopedias, NASA, and other authoritarian sources without question in order to form their worldviews. Some folks even give NASA some sacred standing of absolute, almost religious faith and trust, forgetting that its is essentially just another wing of the US Government and Pentagon, which of course is only interested in truth and the betterment of humanity... right?