How is looking
at the Earth
from above
a fantasy?

In the most obvious sense, it is a fantasy in the sense that it is unachieveable. At least for the everyday person, we still don't have common access to aircraft able to take us to such heights. However, it is also a fantasy in the sense that it is a dream that we aspire to. For most of human existence we have fantasized, in a pictorial and spoken manner, what the planet we reside on looks like.

We placed our gods in a realm far above our own because that was deemed a space impossible to enter.
So now that a select few have floated in space with a total view of planet Earth, what is the next fantasy?

Earth from above has a sense of fantasy due to its unthinkable reach. As you said it's something that is unachieveable to the every day person. The idea of placing gods in a realm far above our own is something I did not think about. It further psuehs the idea of "fantasies". Who knows, maybe the next fantast might be unlocking a new dimension?