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Nintendo always does something that's JUST slightly off with their consoles that make them annoying as hell to use. With the switch it's the screwed up USB-C implementation and the fact that you can't use bluetooth headphones (it has BT support, but only for the controllers) With the DS, the wifi only supported WEP, not WPA, even though WPA2 had been released by the time the DS came out The Wii famously didn't suppor…
The Switch was updated to support BT headphones, with the caveat that you can only have 2 BT controllers simultaneously connected with the headphones, and the controllers can’t be switched while headphones are in.
Multiple devices on one Bluetooth controller have to timeslice in 4 millisecond (iirc) chunks. Audio devices in a high quality mode consume a substantial amount of the overall bandwidth. It also doesn't matter if your packet consumes the full size of a chunk of not, all of them are equally sized. You'd have to do two audio chunks and one controller chunk * 2 controllers to maintain a 60 Hz sample rate on the controllers.