Uhhh, Physics are indeed a major part of Teardown. the breaking of the Voxels themselves may not be individually impressive, but it's the nearly entirely destructible Environment with per Voxel calculated Materials that IS impressive.
Voxels can be of a wide range of Materials, giving them, well, unique properties. that allows things to be strong, weak, and all sorts of other properties.
Driving a Truck through a Building doesn't leave it unscathed, actually. Et Cetera.