From a certain perspective, the concept of a sky castle is not very practical.
After all, if you have the capacity to build a city that floats in the sky, wouldn't it be better to use that productivity for something else rather than constructing a floating city?
But on the other hand, when your productivity has reached the level that allows for the construction of a floating city, then your technology and production level have undoubtedly achieved a remarkably advanced state.
It's like building a giant humanoid robot; its practical combat performance has always been criticized in the original world, and creating humanoid forms requires much higher technical demands than creating other shapes.
But conversely, if you can create a giant humanoid robot, wouldn't you be able to create something more practical?
Ultimately, it's only after technological development reaches a certain level that one can pursue the extravagant after solving issues of existence.
