There will be no measurements. It will be my observations with help of my beloved Ears and biased Mind
This is not a valid way to draw a conclusion. For each person you can find that can hear a change, I could find that can't. It doesn't make either conclusion right or wrong.
But if we understand how frequency response can change, we can recognize that USB conductor material is not capable of affecting this change, and verify it with measurements. It is the only valid way to determine the facts.
Anything else is pure speculation, with no factual support. It is misleading to people who come here for advice. And to use such unfounded methods to advise individuals to spend sometimes exorbitant amounts of money for cabling is nothing less than wanton recklessness.