One thing I'd like to add is that the author of the piece didn't mention his method of watching movies (that I can recall). Since most people stream nowadays, that could also be a factor. The reason I bring this up is that I just had my LG OLED TV repaired and besides replacing the screen, one of the command modules was replaced. This processor controls lots of functions with the pixel refreshing feature being one of them and it was not doing it's job, leading to some pretty bad image retention.
When it was all done and set back up, not only was the picture fantastic, but so was the sound. It was much improved, especially in regards to dialogue and intelligibility. All I use is a soundbar and it was better in all respects.
This lead me to think that a potential bottleneck could be the processor used to handle the sound in a mass produced TV. One made with cost cutting tech just good enough to do the job and nothing approaching SOTA. Just replacing the unit with a new and improved one (that looked nothing like the old one) made for a big leap in performance.
With all the constant improvements with streaming audio I don't see why the audio portion of a TV should be overlooked. No matter what one has downstream of it, it's literally a great example of garbage in, garbage out.
All the best,
Nonoise