the essentials. I don't think there is due much concern in this area with brand, etc. The brand of headphones is important to performance you get. Extending the wire only needs basic quality & size wire cable with undamaged connectors at the ends.

Yes, there is SOME quality differentiation in the industry. For instance Belden points out its product of longer strand filaments is more supple than cheaper short strand stuff.

Yes, there are extreme audiophile out there who pay even a thousand bucks & more for an exotic. That group lives in their own little enclave of privilege. If they help by paying decent tax rates, good for them.