You wanted a reference and you got one.
Btw, you post included:
"Listening tests are subjective"
and i cited it and reported another point of view wrt your statement.
I responded to your post, gave an example for an audio field that follows the same approach as you did and then i reported another point of view, where the authors explained why they think a listening test is objective (if done in a sound way).
Of course it is an opinion piece in which the authors argue why they consider listening tests (if representing good scientific practice) as being objective. Their headline included the question "are listening tests subjective?"
You are mistaken; that´s not the authors point. The author´s point is that, if you use a listener as a detector in a good scientific test then this test should be considered as objective because the test is valid, reliable and objective (within the limits of the detector).
It´s the other way round, as the authors indeed said in their next to last paragraph (translation by me):
"Suggested Terminology
It seems to be sensible not to differentiate between "objective" and "subjective" but instead to discern between "technical" and "perceptual" or between "physical" and "psychological" measurements. As the objectivity can be ensured by carefully and reproduceable execution for both, is it important to evaluate which degree of validity and reliability is needed wrt to the hypothesis under research"
Obviously the authors realized that their proposed terminology wasn´t accepted by the majority (up to now?)!?
If someone uses the terminology "measurements and perceptual evaluation" i assume that most (if not all) real researchers understand what is meant.....