I'm not sure what there is to say about cables that would convince the believers, and for the manufacturers and their various hangers on there is far too much money in purveying snake oil to ever desist. The sellers are quite clever in grabbing onto a few truths or half truths to provide a foundation of sorts which can then be distorted and added onto by hyperbole, spin and in my opinion outright lies. For example, cables do make a difference, the cable has to be suitable for its intended duty (such as gauge), however that's not a cost issue (not at audio level, it's a little different when you get into stuff like HV transmission cables) and the cheapest cable out there of the right gauge will be quite sufficient. Connectors do make a difference, a good, tight connection (but not so tight you'll never get it off except by destroying something) is better in terms of the electrical link between cable and connection. Good quality connectors should also be more durable, but again you really don't have to pay much for good connectors. The infamous skin effect is real, and not a fiction dreamt u by audio cable makers, however it is misrepresented to a point by which I'd consider most of the nonsense spouted about the skin effect by audio cable makers to be disingenuous at best and should not be believed. As on so many other subjects Peter Aczel was right when he summed up cables thus:
Cables—that’s one subject I can’t discuss calmly. Even after all these years, I still fly into a rage when I read “$900 per foot” or “$5200 the pair.” That’s an obscenity, a despicable extortion exploiting the inability of moneyed audiophiles to deal with the laws of physics. The transmission of electrical signals through a wire is governed by resistance, inductance, and capacitance (R, L, and C). That’s all, folks! (At least that’s all at audio frequencies. At radio frequencies the geometry of the cable begins to have certain effects.) An audio signal has no idea whether it is passing through expensive or inexpensive RLC. It retains its purity or impurity regardless. There may be some expensive cables that sound “different” because they have crazy RLC characteristics that cause significant changes in frequency response. That’s what you hear, not the $900 per foot. And what about the wiring inside your loudspeakers, inside your amplifiers, inside your other components? What you don’t see doesn’t count, doesn’t have to be upgraded for megabucks? What about the miles of AC wiring from the power station to your house and inside your walls? Only the six-foot length of the thousand-dollar power cord counts? The lack of common sense in the high-end audio market drives me to despair.
There are certain companies who exist on scamming the gullible and from what I can see offer nothing whatsoever of any value to anyone other than their owners who are creaming it in (eg. Nordost). There are others who if they want to can make a good product but prefer to make the easy bucks by selling snake oil cables etc, for example I was actually impressed by the AQ headphones they made which have now been discontinued. I was very friendly with a chap who owned a hi-fi store and who sold me quite a lot over the years and always gave me terrific service. He sold some of this rubbish, I used to joke about it and sort of question why a good shop would sell stuff which was just over priced tat and he always had the honesty (to me at least, probably not to people buying said tat) that he was a shop owner in it to make a living and if his customers wanted that crap he'd sell it to them.