Norghaus mis identified the singularity

In a 2015 paper, Nordhaus reasoned that the Singularity would be necessarily preceded by ever greater technological progress that would accelerate the replacement of human labor by automation. More work would be accomplished with less labor, so the level of productivity would rise. But in actual fact, he noted, productivity has been in the doldrums for a long time, and there seems to be no systematic rise in unemployment.

There will be less unemployment with the singularity, the singularity keeps folks busy.  The singularity will not be about walking humanoids, the singularity doesn't simulate humans, it has about 8 billion people to employ.  Bots like people, they are self generating bio-robots with mobility and opposing thumbs for grasping.

Productivity will be slow for a while as the singularity learns more about our wants and desires.