I'll try my best Roger. First let me say this isn't a what's better thing since it can also explain why analog sounds bad in extreme nearfield and with headphones just as it does why it sounds better to many from near/mid to mid/far field.
While I've had hundreds and hundreds of hours behind consoles the bulk of that time was focused on sound for TV and film and not music. Matching what is heard to visual pegs sets rather tight reign on artistic license. Take dialog replacement. While the voiceover talent is close miked in an isolation booth, you have to adjust the sound of the voice to match the distance of the actor from the camera. The same thing happens not just for dialog and sound effects. You have to match the ambient field to that of what's on screen. The two principal tools for this are to overlay a room tone and to set appropriate reverberation times for the size of the scene's location. Floating in Space? No room tone, zero reverb. Tom Hanks in the Vatican? Room tone lower, reverb time long. Etc.
Interestingly Mark says "seems to go on forever" and Roger says "completeness" due to having set boundaries. Tom goes and describes the distortion behavior of the mediums but this is a smaller part of it. Now we know it really doesn't go on forever. We are however looking at the manner in which the highs decay or more precisely the nature of the noise floor that they decay into. Which really boils down to the noise floor of your listening window or a noise floor determined by your system. Sounds crazy I know but let me try and explain further.
When setting the ambient sound field for film, the room tone is set to dominate or override the room tone of your own room. It, in Roger's words, sets the boundaries for the location of the events. As such the decays sound more natural "go on forever" because it dives into a noise floor that is consistent. When watching a movie with headphones the hash of the room tone can be quite unpleasant and fatiguing without one knowing that there really is this noise put there on purpose. We filter out this type of noise anyway 24/7 from the day we were born to the day we die. When it goes missing however, it's a creepy unnatural feeling. There is such a thing as too quiet, we all know that.
Interestingly enough, groove noise and groove echo as well as tape hiss are very, very similar to room tone. Enough to set a self contained set of boundaries, fill in dead gaps in space. Attempts to actually minimize groove noise like 80's Japanese Press JVC LPs and the use of ever smaller stylus profiles (think Clearaudio cartss up to about 2 years ago) have been criticized as sounding clinical which actually should be understood as not too detailed but rather "too clean" or "too precise". One can never have too much detail after all, it just has to be natural sounding detail because in real life we aren't in anechoic chambers.
So I've put myself in a pickle. I've just said that Analog adds stuff that makes it sound better. Yes I did. It can be argued that because of this, analog is not accurate. Before the war begins just let me remind the digital camp about what happens inside our DACs. Noise is added on purpose too. So the argument goes both ways. One thing for sure is, noise done right is not a bad thing. Not bad at all.
Noise is your friend