What you are describing is exactly what Apple’s W1 chip does. Pair once with any of your iDevices, and you can then switch sources with a one or two taps/clicks

What you are describing is exactly what Apple’s W1 chip does. Pair once with any of your iDevices, and you can then switch sources with a one or two taps/clicks. Of course this requires you to be firmly in the Apple ecosystem, and the AirPods are deficient in both audio quality and noise isolation, but the ‘ease-of-use’ problem has been solved.