The joy comes from the brilliant attempt to break the hegemony of our visually dominated culture, as hearing has a greater information content and is harder to fool than vision. As the speaker claims, verbal communication is the greatest breakthrough in human evolution.
The sadness is because it is based on flawed audiological and psycho-acoustical models that derive from the biggest selection bias in the history of science: measuring human hearing capability of neural circuitry trained on the universal temporal and spatial distortions of audio.
Because of this, this research and product are part of the vicious circle preventing the transmission, storage, and reproduction of sound as we were evolved to perceive it.