OK, calculation time. A regular 2-tier rack like you can see everywhere fits around 2 bikes per 0.8m2, so about 34 bikes in 14m2.
Reference used for calculations : https://cycle-works.com/products/josta-2-tier-rack/ (it isn't even the most compact design you could find, but it's a common model and the documentation is readily available)
Both numbers don't take into account the area required for access and maneuvering. Admittedly this number might be lower for the rotating system that you can only access from one side. Still, considering all the pros and cons, it still baffles me why anyone would go with a more complex, more expensive, less accessible, and overall less capable system.