First the usual consideration of mechanical construction and production runs; stopping the plastic from rattling and making headphones comfortable adds to the cost.
Then there is bulk; the transformer+caps arrangement is large and heavy, incurring cost all the way along the supply chain.
Then you get into arguments about how much distortion is OK; you can never get to zero but you can asymptotically approach it at increasing cost.
Personally I bought a Sabaj A3 for my TV, which is about $120 and has TOSLINK and Bluetooth. No audiophile will ever use bluetooth, but for playing music in the lounge it's completely fine.
Well, sure there are audiophiles who are gear fetishists to a stupid extreme. But bluetooth, ugh.. Sketchy, bad latency, audio distortion, weird time jitter. Companies are making things like bluetooth midi controllers, but I can't imagine ever, ever, ever.. bringing bluetooth on stage for a gig.
No, it's because audiophiles know you can't apply digital compression and still retain musical accuracy. The initial bluetooth specs didn't have enough bandwidth for uncompressed audio, so they mandated a non-standard compression.
Audiophiles may know that, but audiophiles are amazing at knowing things that aren’t true. A good modern codec at a moderate rate is indistinguishable from uncompressed audio. Bluetooth, sadly, isn’t one of these.
I work in film post production/audio as a freelance mixing engineer. While I have a certain amazement at stuff audiophiles will claim to hear, hearing the difference between compressed and uncompressed is certainly not impossible, but it depends on the signal you use to compare.
I am a cables person, but for me this is more about reliability and ease of use than sound. When I disconnect the cable stuff it ends. When I connect it and I don't use cheap or broken cables they just work. And they also work with somebody elses gear.
There is a reason professional wireless receiver/transmitter bodypacks cost upwards 500€ per pair.
I used to be able to reliably distinguish 128kbps MP3s encoded with some mediocre encoder from the original audio (blinded, but I never tried double-blinded). I doubt I could pull off the same stunt with a top-of-the-line encoder, let alone with a better codec at an appropriate bit rate. A good codec can be made “transparent” such that no one call hear the difference except perhaps with deliberately chosen music that abuses that codec.
Now if only the world could settle on actually using good codecs...
I agree. If you use OPUS for example, it becomes nearly impossible to tell.
But one thing we should not forget: these codecs are used for distribution or streaming. If you ever record something that has to be edited, filtered, treated with an EQ, denoised etc. then go for at least 24 Bit Wav. Compressed audio is great for when the thing already sounds the way it should, but it starts to fall apart very quickly when you manipulate it heavily.
Then there is bulk; the transformer+caps arrangement is large and heavy, incurring cost all the way along the supply chain.
Then you get into arguments about how much distortion is OK; you can never get to zero but you can asymptotically approach it at increasing cost.
Personally I bought a Sabaj A3 for my TV, which is about $120 and has TOSLINK and Bluetooth. No audiophile will ever use bluetooth, but for playing music in the lounge it's completely fine.