I think this is the rice protein that is used in Soylent.
Several of us have speculated that’s the case - usually based on the claim that Soylent has a rice protein with a complete amino acid protein profile. Oryzatein is the biggest commercial product that fits the description.
If you saw the CBS interview, there was a shot of a powder with a label "rice protein \n (Axiom)"
Just after the 2:30 mark