I don't think you can draw that conclusion. The table that Pete put up simply shows the electrical conductivity of the various metal in response to a specific question.
In theory a difference in pure conductivity should not make a sonic difference as it is linear across all frequencies and would therefor affect all of the signal in the same way (although I suppose the even a linear lowering of the signal amplitude could end up obscuring small details.)
However we as audiophiles know that nothing is ever as simple as the pure theory would lead us to believe as there are always other factors in play.
This is kind os a long winded way of saying that each type of metal and plating can have a different sound to it and therefor none can really be called the "best" overall. Each one can have an advantage on matching different combinations of components in different systems. No component or system is perfect, so different materials will help (or hurt) in different situations.
As always, synergy, synergy, synergy.
It makes me wonder, how much of what we hear (as far as cables) is the sound of the metal vs the sound of mismatching various metals, Including the plating?
Basically the whole supply runs on heavily shielded aluminum into your fuse box (pretty sure anyways?) Then we have solid core copper to the outlet. The outlet could be aluminum or copper - plated somehow. From the outlet to system it varies (obviousily)
It almost makes me wonder if running aluminum right through might clear up any discourse. So it asks the question how far back is audibility of wiring material go. Would our systems sound different if we used copper from the transformer into one's house? IDK but i am inclined to say yes. To me it seems silly that PCs can effect sound and then stop at that and not look at wiring right from the Power generator plant.