It's more of a worn-out trope by this point and better skipped. Just sneerfully flag lame comments.
Dark [Rubik's] Magic that they are.
Like someone saying “less space than a nomad. Lame.”
I agree with the other commenter that a normal 3D cube feels much more intuitive and simple. I guess it's just personal preference/thinking style.
But it is not one of the cubes that need to go to their correct locations. The center cube is not moved by any operation on the cube; it is always in its correct location.
(At least, that's true of the 26 outer cubes. You can't get them all into place without simultaneously aligning them correctly. I don't actually know if correct alignment of the center cube is also required, but it'd be my first guess.)
Nobody believes there are invisible cubes outside the Rubik's cube. That's not the same logic; that's you trying and failing to imagine a problem with the idea that cutting a cube into three parts along each of its three axes will generate a hidden central subcube.
You got 26 cubes in 3D space that need to go to their correct locations. They can move in 3 axis. They are color coded for recognition.
I think anyone is able to solve the first 2 layers intuitively. Just start by following one of those 26 little cubes and see how it moves about.