For a start, having AirPlay functionality doesn't guarantee the speaker will sound great or be compatible with all devices. Be wary of which speaker ... design and features will help you find the best ...
To use AirPlay, you'll need a compatible Roku TV or streamer ... Note that Roku and smart TVs require AirPlay 2 on your Apple ...
The second iOS 12 beta has gone beyond just spotting the AirPort Express in the Home app, adding more weight to speculation that the discontinued device will be an AirPlay 2 target in the future.