This stairway is part of the Tokotah buildings. It hasn't been made solid by Cyan. It's one of their many unfinished projects. At the top of those stairs, the balcony textures are unfinished.
It's like the upper section (where the disco is) over Tokotah Courtyard in the stalagmite range. One could think it's TOC team who carved this whole section and made a floor and even made a spiral path in a high stalagmite. Nope... It's all Cyan's work. TOC team only made it solid and add a bridge.
I would say 95% of what you can explore in COD was made by Cyan in the first place. The roofs, the balconies, the locations, the stairs, the rooms, etc. The major issue with Ae'gura is that we can only travel through less than 5% of the whole surface Cyan made which is really a robbery

. In COD, we can almost visit everything (with jump command)
