> Airplay doesn't offer multi-room audio; AirPlay 2 does
> AirPlay lets you stream from any Apple device to your speakers or TV
> AirPlay 2 lets you play from speakers over Wi-Fi, and it'll stay in sync
> AirPlay 2 lets play different songs in different rooms with multiple HomePods
Personally I've been very happy using AirPlay 2 with recent iPhones, a collection of HomePod Minis, an AppleTV and Denon Receiver. It makes it pretty easy to set up complex audio routing configurations from your phone. You can send a stream to several devices simultaneously while controlling volume independently and as a group. You can see what's playing on each device. Audio quality is good, battery impact seems fine.
I wish I could have strong AirPlay 2 support from non-Apple devices, but I know how the ecosystem works. Still, easy enough to use something like the Emby iOS app [1] to bridge arbitrary content into the system.
[0] https://www.pocket-lint.com/speakers/news/apple/144646-apple...