I thought I read somewhere where there is a shaft, but it isn't big enough to handle the full height of the building. It's hard to say with the fail of journalism, today, which is right. It's obvious the building DOES have an elevator, just not something that can service the whole building.
Not being an architect or an engineer I am just speculating here but...
1) I think that the size of the shaft (dimensions) is sort of not relevant.
2) I think that it comes down to a building structure issue. That is, the way that the structure is built in order to support the weight of the car, its passengers, the motor that drives the car, the cables that connect the car to the motor and the other items (rails, doors, etc.) that are all attached to the shaft.
Also, there has to be a theoretical maximum height for any shaft because at that point the weight of the car, passengers and cables become too heavy for a cable of practical thickness to support. When that maximum height is reached the solution is to then create a midpoint elevator lobby with a new shaft arrangement to continue to the top of the structure.
Still, this would be like building a cruise ship and forgetting to put in the kitchens that go with the dining rooms.