What's the intended use case for a device like that? Like, ultimately my headphones are still wired into a device I need to carry around, and Bluetooth isn't good enough for me to be able to walk too far away from wherever my phone has ended up.
They also don’t use standard bluetooth codecs, they use a different “HiFi” codec (I don’t know the details; but it’s significantly higher quality audio), and the range is pretty good - across the house or further for me.