I think it's maybe notable that, when you get into discussions about objectivity in the fields of ethics or metaphysics, lots of people seem to admit that both of these things can be infinitely reduced to the point of practical relativity, but nonetheless it's, sort of, a waste of time to do so. It's a useless practice that will end in a cyclical argument and doesn't get us anywhere so you have to, kind of, draw your line in the sand somewhere.
In the case of objectivity in art, however, it's the general consensus that any claim of objectivity is simply off the table. Has anyone else noticed this inconsistency? Or am I, perhaps, missing something?

Imagine if you were a musician and you were to go into a recording studio, and anytime you try to talk about or work on anything in that situation, one guy in the band were to only talk about how soundwaves travel through the air, how they work as electrical signals in cables, the mixing board, etc.

That's fine and it's certainly a factor that everyone is aware of to some extent, but if that guy seems to ONLY be able to talk about that, he'd drive you crazy--you'd think something is wrong with him, in some sort of weird OCD or autistic/Aspie/"idiot savant" way, and it would be frustrating in that you'd not be able to work on anything with him, because he just constantly obsesses on soundwaves and how electrical signals in cables amount to sound transmission.

That's what it's like when people keep obsessing on epistemology, semantics/semiotics, etc. regardless of what topic you're talking about. — Terrapin Station

I mean this is a forum about idealism.

But there is a practical point in putting forward these kinds of views. For example, I might think that creating art is the supreme purpose of life and is more important than, say, science. Or I might think that there is a God. There's only a point in pointing out that all of these things; logic, mathematics, ethics are reducible to a subjective viewpoint if someone is trying to tell me that I'm objectively wrong.

And I think the prevalent, accepted view of our times is that science is the supreme authority on everything. We have a kind of reverence for the scientific method. We believe in pursuing a constant search for scientific 'truth' regardless of whether it has any agreed-upon usefulness.
Insofar as we can all agree that it's on our side there's no reason to question it: we're all agreeing to take the same leap of faith. But, in cases where it isn't, it's necessary to take it down a peg or two by reminding everyone that it has no more objective truth to it than any other ridiculous worldview.

I particularly think this when I see scientists scoffing at religion. (I'm not religious, by the way, I don't have a horse in this race.)