The experience of vastness is mostly due to (high-res) stereoscopic vision. When you experience 6DOF VR in a fairly high-res world it definitely comes much, much closer to the awe one feels with the real experience.
It's similar in dismissing artificial audio based on listening to some pop song on a basic mobile speaker versus listening to well-designed binaural audio on good headphones. The latter can sound 'freakily' 'real'.