(Martin Behaim and his Globe)
Interestingly, Erdapfel literally translates as "Earth Apple". According to Wikipedia this may relate to the Globus cruciger - the holy orb topped with a crucifix that is often held by kings and rulers as a symbol of power. In the German language this orb is called the Reichsapfel - meaning "Empire Apple" or "Imperial Apple".
I've actually seen this link between the royal orb and the globe made on some of the Flat Earth videos I've watched, so I guess it isn't anything new. The general theme being that the globe is used as a concept of control. Setting the boundaries of the political domain and the boundaries of our thinking.
I can't help but think of the apple in the Garden of Eden - assuming it was an apple of course. Was Eve given knowledge of the earth being a globe? Was that the secret the serpent whispered? It would be quite fitting come to think of it. A symbolic journey from the flat, godly garden managed by the almighty to the godless, godforsaken wilderness of the infinite universe.
Flat Earth in many ways is the Garden of Eden. A managed finite space, a wildlife sanctuary for God's pet humans. A beautiful place created especially for us. Leaving that world view means stepping into a world that wasn't created for us. A world where we aren't the focus. Where no-one is looking after us, keeping an eye on things.
The apple is knowledge, the globe is knowledge. Now you have that knowledge you're cast out on your own. A lonely lost species on a loose blue marble. Not even sure if up is up and down is down.