>... 33 'Yes' or 'No' general questions that, when answered correctly, uniquely identified everyone on the planet.

I think a lot is possible with this challenge. You could compress over 8 billion yes/no questions in a single yes/no question under these rules.

And if that doesn't neatly divide people, why not let the people divide themselves through unique thought?

A 33-bit hash would probably collide too much. Yet there seems no requirement to communicate your hash back to the creator of the questionnaire with your answers. It could be a 1024-bit hash of a short story like:

  Hi I am blauwbilgorgel. I currently define myself as male.
  My internet names are ... I lived at ... I think we are
  in Time Cube. Today is Setting Orange. I declare ...

that would create a unique hash with which to uniquely identify yourself with.