“…for dedicated audiophiles who sometimes change their equipment, it is good to treat a selection of cables as tools in a tool kit for final tuning.”
I agree, and with the rest of your post too.
The cables need not be expensive but it helps if they are different and bring their own unique strengths. For example, I keep SCs by Harmonic Tech (lots of OCC copper, fine gauge solid core, and individually insulated), Furutech (super fine strands of OCC copper in foamed PE), and NOS WE (annealed, tinned, stranded copper), and a few others that all result in a subtly different sound. Same type of deal with PCs and ICs.