> This test is the one metric we have for precisely judging whether we're capable of making fully-simulated footage that can be classified as real.
You are completely misunderstanding this topic area. We already know how to compute ground truth references based on the real physics. I suggest starting with the book Physically Based Rendering.
The question now is, how close can we get a real time approximation to match unbiased path tracing? The OP's link is a pretty definitive step along this direction. But even if that whole research agenda fails, so long as we keep getting more computation at a cheaper price, even unbiased renderers will become real time.
You are completely misunderstanding this topic area. We already know how to compute ground truth references based on the real physics. I suggest starting with the book Physically Based Rendering.
The question now is, how close can we get a real time approximation to match unbiased path tracing? The OP's link is a pretty definitive step along this direction. But even if that whole research agenda fails, so long as we keep getting more computation at a cheaper price, even unbiased renderers will become real time.