There seems to be some confusion going on between characteristic impedance and "regular" impedance. Although both are measured in ohms, they are mostly unrelated.
I remember during my grad school days seeing a series of articles in Audio Amateur (the ancestor of my current publisher) by Dick Marsh where he conflated characteristic impedance with impedance when discussing how to run grounds in a preamp. Now at the time, I was teaching an E&M class and wondered a lot if I really understood what I was doing- after all, this was a big name publishing in an excellent magazine and I was a young pup. Then after reading it carefully and running some basic experiments, I realized that either the author didn't know what he was talking about, or he did and put that stuff in to make things seem more black magic-y.
Over the years, I came to the realization that he probably started out completely honestly confused, then later figured out his error (or had it pointed out to him), but then transitioned into encouraging this kind of confusion as part of his black magic hype which made him money. This seems to be an extremely common pattern in fashion audio.