I've given this some thought. I have a theory why cables are more important in a playback system than in the studio.
Imagine standing in front of a live, acoustic band. Close your eyes and you can place the location of each of the instruments. That is because of phasing. This live band with several sources of sound is a jumble of frequencies and phasing. But even though the phasing is different this is how we can tell with our ears location- left, right, up, down, front, and back of all of the different sounds. This jumble of phasing from all of the various sources on stage sounds natural to us because this is our physical world. Phasing does not change with distance. Only amplitude changes with distance. And yes, high frequencies get dampened faster. So we all find our favorite spots to sit in a concert venue. Some like the front rows for a louder, more engaging concert, others like the middle rows for a balanced sound and some prefer the back rows for a more relaxed presentation. It's a matter of taste. While everyone is experiencing either a brighter or more mellow sound depending on seating position they are all experiencing the same phasing of the sound.
Put this band in a studio with multiple mics and pickups and now the studio must faithfully preserve this sound in a recording. As long as the microphone cables and pickup cables are identical then the phasing should be preserved. Note that no high powered amplifiers are used in the recording chain. That is a significant difference between studio and playback. (I'm not counting the high powered amplifiers used in the cutting lathes for making vinyl records). As long as the studio preamps and equalizers preserve phasing then the fidelity of the recording is maintained. Of course patch cords between preamps to recording device play a significant role in preserving fidelity but only after the recording is down mixed from multiple channels to two channels. And I think power cords, quality of power coming into the studio is just as critical as it is in a playback system. Any phasing information, any detail that is lost during the recording process is lost forever. So one question is: How much care do studios take in the use of power cords?
Now the playback system has the task of reassembling not just frequency and amplitude information but the all too important phasing information. The quality of reassembling the phasing information directly correlates to the realism and naturalness of the reproduced music. Most, not all of that responsibility falls to the speakers with the second most important component being the cables. The cables, being wires can't help themselves. They move signals at different speeds relative to frequency. Yes, sound waves move through the air at different speeds relative to frequency but the proportions between electrical wires and air is much different. So cables can alter the phase information in the musical recording. To complicate that, any speaker that is not a one way design such as a Quad ESL, has a crossover network that splits the frequency range of music and directs it to different drivers design to reproduce a specific range of frequencies providing more challenges to the preservation of phasing of the original music. So our playback cables not only need to reject noise, interference from the outside, but also try to maintain phasing as these signals traverse the wire. We see cables with network boxes and others that use a blend of dielectrics and wire materials to preserve phasing. I think that we find some wires work better with certain speakers than others because the cables need to compliment the crossovers with respect to phasing and also frequency response.
This is somewhat simplistic but still too long. The magic of it all to me is how I hear a 3D soundstage (left, right, front, back, up and down) as if the band is right there in front of me. But at the same time some of our hifi systems sound more real than real. It's not really hifi then, is it? What I mean is I can feel, not just hear the plucks on guitar strings- maybe in real life I'm sitting 3 feet from the guitar player. Or I hear clarity beyond what can be heard at a live session. It is the same as watching our HDTV's. We all, at least I do, have the color saturation, the contrast and the sharpness cranked up so that the picture looks more real than real. HDR was supposed to give us a more true rendition of the scene. HDR stinks.