Perhaps true, but I think we can all agree that copper wiring is more convenient.

I dunno, reading the article it seems like a flawed experiment? The audio wasn't played back through those mediums but recorded through it and uploaded to a forum. I might've missed what software was used to do the recording but a lot of ADCs have some built in high-pass/low-pass filtering that could remove noise. I'd be interested in the audio played back through them to headphones cause that would sound like shit

This gets proven over and over again, people will continue to believe what they want. The only thing to spend money on with audio cables is build quality but the promise of improved audio quality is a siren song.