Sure, the stairway is very long. However, besides the fact that I did not really know how to depict the switchbacks you describe, the in-world justification is that it is build there in that way because the terrain itself was more favourable in that point. It is also quite wide, which would have been difficult to obtain if it was laterally carved in the cliff, and given the relatively low steepness, it should not be too bad. It should also be consider that every step is meters long. Picture this kind of stairway, only much longer. It can definitely be travelled by horses etc. if one does not feel like walking. Also, it is an utility staircase, I don't think these people would be too interested in scenic vistas when going around their businesses.