The biggest thing that bothers me in Bluetooth is the lossy audio compression

3. Manufacturers forcing you to install their (adware infested) mobile apps to remap or use the hardware buttons

Sony xm4 and xm5 have dual connectivity.

Dual connectivity on the XM4 is horribly broken for me. As soon as you try to use the mic, nothing works reliably anymore : the headset randomly stays blocked on one profile on another and you invariably end up with either crappy sound for your music or no voice for your zoom call.

Now I use it exclusively on my phone for music and I have another headset for voice calls on my computer. Which is a shame given how much money I had to throw to buy this thing.

Still, I have to acknowledge, sound is awesome, so that’s why I keep it anyway.

AAC and LDAC should be good. I even use them with PipeWire. Once you switch the mic on though, you end up with a different (low quality) audio profile. It should switch back to high quality profile after but I guess it does not?

Also does dual connectivity even work with LDAC? I feel like the best way is to use software to connect manually. You do have to specify the address and such, and execute the action, and you have to disable Bluetooth when you don't use it. Advantages are less tracking and interference.

As for XM5 it is expensive compared to XM3 and XM4. If you want to spend that extra money there are better targets (victims of current war for example).

Same with Bose. But I have two desktops and a phone, and never know which two are connected. Why limit it to two? Seems arbitrary and unnecessarily limiting.

Generally multiple bluetooth signals seems to degrade the overall audio quality.

The AirPods are the only product in the same class that can sort of link to more than 2 devices... but all of them need to be apple.

They don't support multiple Bluetooth audio connection at the same. They basically quick switch between devices in the background.

I'd be fine with that. The Bose headphones seem to be doing something similar as only one device can play audio at a time.