It works natively with Apple Music on Apple devices. The Wiim doesn’t have an Apple Music app. Last I checked, Apple Music was the 2nd largest music service, so it is a big deal to many to not have AirPlay on a modern streaming device.
AirPlay 2 allows for the device to be used in multiroom Audio at the Control Center level, as well… with all music apps.
AirPlay 1 would be my choice even if I lost multiroom audio from the control center because it would allow for lossless. I wonder if Wiim has looked into AirPlay 1 certification? There are other streamers out there still using AirPlay 1.
As I mentioned, if you can link two Wiim devices, it’s a back door to resolving the issue wirelessly.