Some would argue cables act as tone controls or frequency filter. I had for some time “problems with boomy bass” and tried all sorts of “fixes”: different sources, positioning of speakers, spikes, damping feet, carpets and what not.
Then I tried different mains cable and I was astonished by the effect they had.
My experience is that they lower the distortion/ noise floor, making it easier to distinguish different instruments and levels of details.
Lower frequencies become cleaner and with a better bass response you experience added space around instruments, allowing for a more “blacker background” if you like.
But we can also look at it from another perspective. Are they worth it? Yes, I believe so. Because the cable manufactures “only” provide us with a tool to fully appreciate our beloved Naim electronics.