Optical viewfinder cameras see through a lens and force-align your eyes, so when you change the lens, what you see is different but highly aligned to what the sensor sees. Here, depending on where you place the thing you see a different thing than the sensor does, the optical path is completely uncontrolled, unless they're doing eye tracking and post processing? This seems somehow worse than a cell phone camera.
As a comparison point, many people shoot street photography "from the hip", aiming the camera at the rough spot they want to get with a forgiving aperture setting (around 8 or more). This help either for speed, or engage with the scene without having to stick a camera on one's face.
I think this camera is basically aimed at the same crowd, those who will want some idea of what the camera is pointed at, but want to stay "in the moment" and no fully focus on the capturing process. This is pretty close to a phone camera perhaps, but I'd assume it's a lot more fun and carefree.
I'd totally love to play with one.