@kota1
The Kota and the Toole are "critically listening" in immersive audio, please enjoy listening however you like over at "dry wall studios".
Dr. Toole is using upmixing for enjoyment, not for evaluating performance of any product. For that, he 1000% believes in testing one speaker at a time in double blind setting, not his home.
For your part, you have failed to explain why you are championing his room when it is a normal living room with hard surfaces and no acoustic products. Dr. Toole is no witness for your case:
"Some reflected sound is good. Sometimes a lot of the right kind is even better. Concert halls are deliberately reflective, highly reverberant, spaces. This is my “classical” listening room in our custom-built Canadian home. Conceived as a space for enjoying large, spatially involving, works of music, it was the largest “concert hall” I could afford at the time. The very neutral, essentially omnidirectional, Mirage M1s “became” the orchestra and the room became a seamless extension of the recorded space. It provided a very satisfying, involving, experience. Because of the designed-in irregular scattering surfaces, the heavy carpet and thick felt underlay brought the reverberation time down to under 0.5s so the room sounded much less “live” than one would think. It was a nice-sounding space, pleasant to be in. Late at night I have been known to sit in the dark with a glass of good Scotch and listen to non-classical involving pieces of music like Dire Straits “Brothers in Arms” played at high level. I miss this room. Elsewhere in the house was a 7-channel home theater with very few reflections but a very good multichannel upmixer and spatial synthesizer, a Lexicon CP-1 – this was 1988."
No one should feel obligated to turn their everyday listening rooms into padded cells and ugly acoustic products. Normal furnishings can act as acoustic features to serve similar purpose per above. Now, if you have a dedicated empty room for music/movie listening, then yes, you do want to put treatment there because otherwise its RT60 will be too high although even that can be cool effect for orchestral or big band music.
The key to good sound in such places is a great speaker. Such a speaker will have off-axis response that is similar to on-axis so the mixing of the two does not cause a problem. Reflections laterally will then sound good and add the feeling of spaciousness which many of us crave.
Please, please don't follow videos/articles from companies selling acoustic products, trying to scare you off with "reflections are bad." Per Dr. Toole statement above, and entire chapter in his book, that is absolutely wrong.