When your body and mind breaks down into pure energy, and is sent across time & space integrating into EVERY single atom and quark of existence, then reassembled into "Normal consciousness", then you will have experienced the unity of consciousness, realizing that you are part of an infinite story, and answering every one of your questions, all at once.
This is possible with or without DMT IMHO, but DMT assures that this is atleast a possibility in my experience.
As far as everyone having different perspectives, yet being unified as one; imagine being a universe that wants to view itself, instead of just watching itself, it creates independent, unique, yet connected consciousness to have experience and observe....itself.

Hope that made sense.
Mushrooms can be very unifying as well.
Hope I answered some of your questions!
Thanks and Praises, Love and Gratitude, Peace and Unity, Hemp Seed & Honey