It took me way too long to figure this out.
Floating is a physical representation of the “mind over matter” idea. When an individual floats, they are showing their ability to conquer reality with pure thought.
When an enlightened person uses their will to elevate other objects and people, it is comparable to the “white man’s burden” to elevate unenlightened savages, animals, and nature.
Tikkun Olam fellow white people, and in the meantime enjoy the low price of cotton, software, and tacos! Isn’t it great how we can have it all? Sweatshops aren’t slavery, if you think about it we’re really helping these people.
If an entire city is floating, this indicates an enlightened civilization.
The earth itself floats in Pandora, the world of Avatar, where extant neanderthals use their blue facepaint a bit more liberally. The implication is that this world is closer to the magic of the dream world, i.e. edenism.
In Final Fantasy 3, when Emperor Gestahl (representing the old Germany defined by Goethe) recaptures the old gods and attempts to turn them to his purposes, a side effect is the temporary elevation of his continent.
When Kefka (representing the Kafka-esque Jewry, lolzzozollolz) whimsically rearranges the old gods, the imbalance releases destructive levels of energy that reshape the world’s continents. The flying continent crumbles into pieces and falls. This represents the two world wars of the 20th century and their effect on Germany and Europe as a whole.
This basic feeling runs so deep that it inspires people to invent fixed-wing aircraft and rockets.