My take is that the key difference is the agency of the viewer; in classic cinema and 3D, the director frames every shot, including depth of field.
In VR, the viewer gets to pick how/what they focus on in a scene.
From my experiences with VR, it works great for set-piece experiences. Anything with a story, though, and there is no guarantee that you will be focusing on the right thing.
In one demo, I was surprised to find out that I was missing out on a bunch of stuff happening behind me.
In a later demo (now hip to the 360 degree thing), I totally missed the entrance of a main character because I was too busy looking behind me; I turned around and POW this thing was already in front of me.
I am not saying that it is doomed to fail; but audiences have no framework to interact with these experiences, and directors lack the visual language.
Fun times though!
