I have no more answers than any of you on the subject of cables, but I suspect there are several variables involved, which can make discussion difficult if we’re not talking about similar variables within our systems.
If you have a separate amp and preamp setup, you’ll have a cable between them. Those who have receivers or integrated amps won’t. So a logical question arises....does the cable between an amp and a preamp behave differently than a cable between a receiver and a CD player? The impedance of the output of one preamp can vary quite a bit from another, as can the input impedance of one amp compared to another. Phono cables have a different set of critical variables that are somewhat dependent on the phono stage and the cartridge loading. We can easily measure the L, C, and R of cables, but how do we measure skin effects, or the differences in metallurgy as it pertains to sonic differences?
All audio gear isn’t created equally either (regardless of the specs). Some systems have superior clarity throughout the whole chain. The clearer a system is, the easier it is to hear minute differences. Other systems have multiple sources that are contributing some form of masking in the chain (likely unbeknownst to the system owner), making it very difficult to hear small differences between cables. That doesn’t necessarily equate to unpleasant sounding, but certainly more difficult to evaluate small changes with.
Cables matter quite a bit in my system, because they make a difference in what I hear. Do I hear differences because I have good hearing? Perhaps, but I doubt it. Hearing is a sense that we simply possess, but listening is a skill that can be honed. I’m pretty sure my listening skills have improved over time even though my hearing isn’t as good as it once was, but it’s also entirely possible that I’d struggle to hear cable differences on some systems.
In the end, our audio experience is such a unique journey that’s very specific and personalized for each of us, that we really need to only satisfy ourselves. I think we should each explore what works or doesn’t work for us in our systems, as opposed to not trying things because someone else who seemingly has more experience told you that you wouldn’t be able to hear a difference.