This is based on what (or who's) criteria? I have nothing to sell. I have no financial dog in the fight. MOTs typically refrain from these discussions for obvious reasons. Unless perhaps they only sell copper for higher profit margins and might have vested interests? This statement may have no truth, but neither do your accusations that anyone that has a different opinion than you has motives other than what's stated.
I already stated the criteria. It is when someone tries to pass off their subjective experience as something more than that. A good recent example comes from macandmar, when he stated, "Its easy to prove, take one copper and one silver interconnect and join an amp/dac together. Trust me if one channel sounds different from the other you will notice."
Here he is talking about "proving" that copper and silver are audibly different. That's going beyond simply relating one's subjective experience and should not be protected by the "subjective" umbrella and should be open to question or challenge.
Let's get back to your original statement. In response to Seann saying that most recordings were done using copper wire, you claimed "Based on economics and not ultimate performance. Copper was 'good enough'." I don't see this claim as being subjective. You say "economics and not ultimate performance" as if to be making some sort of objective claim, and then add "good enough" in some rather derogatory quotes. You say "Science says silver is a better conductor than copper." Well, silver does have slightly higher conductivity compared to copper, but when it comes down to a cable, that just translates into simple resistance. You could just use a little bit more copper and achieve the same resistance as a given wire made of silver. So would you say such a copper cable would have the same "ultimate performance" as a silver cable?
What drives me crazy are people who say they are "subjective," but make objective claims.