I am honestly of the belief that there is some other difference that the cables make that we simply can't measure. Just like how no graph can measure the "detail" of a headphone, there is something else that we don't simply understand that changes how it sounds.Cables also have electromagnetic properties and are incredibly sensitive to IEMs more so than headphones. While the basic concept of electrical engineering do not explain its predictive effects on a very small scale (just millivolt differences between cables when music gets complex), our ears are sensitive enough to hear those traits.
In the end I have to go by ear to judge a cable, and just like trying a headphone on multiple chains, it's best to try a cable on multiple headphones. But also the value proposition for high end cables is really not there... but obsessed audiophiles we are