Good article by the way. And yes i believe in Flat Earth theory. I cannot explain why but i think its possible, there are some evidence in Holy Bible that earth has 4 corners:
( Ezekiel 7:2 “Son of man, this is what the Sovereign Lord says to the land of Israel: “‘The end! The end has come upon the four corners of the land!)

(Revelation 7:1 [ 144,000 Sealed ] After this I saw four angels standing at the four corners of the earth, holding back the four winds of the earth to prevent any wind from blowing on the land or on the sea or on any tree.

Revelation 20:8 and will go out to deceive the nations in the four corners of the earth—Gog and Magog—and to gather them for battle. In number they are like the sand on the seashore.)

Of course if you believe in bible.
And that earth doesn't move it is still. And it has a borders . Like big ice wall . I cant give any proof but fact is that no human has crossed south pole and plains has no permissions to fly over it because excuse is that engines just freeze . And why all world has agreed that south pole will not belong to anyone. Anyway in reality it does not change anything do some one believe in that or not its their own choice.