User blog comment:B1littlehero/Speculation of the Origin of Species/@comment-7622429-20140612021301/@comment-160529-20140612030327

I dont believe that they are undead... I said that their ancestors were corpses brought to life. I dont even think that the forces of the city have knowledge of the origins of the Exos or Awoken, I am pretty sure that these are mysteries meant to be uncovered.

Saying it would be "controversial in-universe" is strange in that case since people... wouldnt know where their ancestors came from.