Legitimately very well done. A self-contained V-slice with attention paid to little details of how things operate around you. Designwise, the fact that you can't ever get to the ground floor despite countless stairs between the first and second strongly evokes "the nameless feeling" that the game is going for.
I had actually been thinking of building something exactly like this for the past few weeks - a giant, BLAME!-inspired megastructure of a procedural airport. Audibly said "no way" when one of my idle Google searches brought me here.