If you take the position that you are Consciousness, all the usual boundaries between you and "not you" become irrelevant. How do we define a boundary between my Consciousness and yours when neither has a physical form or location? In fact, the very concept of boundaries comes from Physical Reality and doesn't necessarily apply to Consciousness.
If the above is true, then there must be only a single, "unified" Consciousness that we all share, not because the boundaries we perceive are illusory but rather because the very concept of boundaries (and hence separateness) doesn't apply to Consciousness. From the perspective of Consciousness, we are all One simply because there is no concept of separateness. In this view, our sense of separateness comes from our identification with Physical Reality, in which separateness really does exist.
If the above is true, how does this play out for us? Since Consciousness is, by definition, something we experience, we need to examine our experiences. So -- what is our experience, if any, of shared Consciousness?