Some of the know something about signal transmission. A lot of them don't appear to. Whether they know something about it or not, what is definitely true is that many, possibly even a majority create marketing material that is full of exaggerations about material differences and geometry differences if not, for lack of a better word, making up how electricity and basic physics work.
However, there is a huge difference between a small difference in electrical transmission and something that is truly audible. I can detect far smaller differences in cable transmission with equipment than what can be heard. It is not even close.
I have been working in professional audio since the late 80s. I have many audiophile friends, many with fairly significant financial means, and my own system is certainly no slouch. I have lost count of the number of time my friends have said these new cables are a huge difference, only for me to show that blind, they couldn't tell the difference from their old cables, or in most cases, much cheaper. We are talking over the years, 50-75. There have been cases with audible speaker cables, and a quick check with the test equipment has shown excessive inductance, capacitance, and even in some cases resistance. For interconnects, we have found the odd poor solder connection too.