@elilla @unixwitch FWIW, there seems to be something very distro-specific to whether Bluetooth works, aside from bluez's general jank of course. I've had the exact same BT+audio+UI stack fail or work on different distros over the years, and so far NixOS has been the only one where it's consistently worked.
That's not to invalidate your complaint of course (this shouldn't be the case!), more to provide some data - it means that presumably there exists some configuration that makes it work reliably.
@ckie @elilla @unixwitch In my case I used KDE Plasma for the whole thing, first on PulseAudio and then on Pipewire, and both worked.