Yes! I was a bit disappointed when he explained it was just portals and a clever rendering hack rather than actually modeling non-Euclidean space natively, then I was delighted when he showed the room-scale VR example.
In mathematics such non-Euclidean spaces are called manifolds. A manifold is defined as a set of Euclidean-like regions that are connected by transition map functions. That formalism is basically the same thing as these portals.
If you take this model but upgrade each cell to a little 3D euclidean region, then you could completely surround it by portals that connect it to the neighbouring cells. The edges of the portals wouldn't be visible. The smaller the euclidean cells, the better the approximation to the hyperbolic plane.
Instead, the goal my engine was to make the effect as subtle as possible, even unnoticeable.
Surely the point of using weird geometries is to expose the player to weird effects that aren't achievable by simple euclidean planes and a bit of trickery with perspective or colours?