Google Hangouts is set to shut down sometime next year, with spin-offs Hangouts Meet and Hangouts Chat intended to be full replacement by then. Even though the new services will technically be available to non-business users, Google is pushing regular people to use Android Messages and Duo instead. As a result, it seems at least one function won't be transitioned to the new Hangouts services — a feature that allowed people to stream video calls to YouTube.
An update to a support page now reveals that Hangouts On Air is "going away later in 2019." The feature allowed people to create a Hangouts call and begin streaming by simply clicking a button, making podcasts and other similar content extremely easy to produce. Google recommends using YouTube Webcam as a replacement, but that only allows one person to go live, not a group of people.
Hangouts On Air originated as a Google+ feature, but later moved to YouTube in August of 2016. It hasn't been noticeably updated since then, except when it joined regular Hangouts in switching to WebRTC for streaming, which allowed it to work in non-Chrome browsers without the use of a plugin. Though, that change is seemingly what caused the On Air Toolbox (a variety of tools for adding effects and overlays) to stop working.
Here at Android Police, we used Hangouts on Air for every episode of the Android Police Podcast until we switched to OBS last year. It seems strange that YouTube wouldn't be interested in developing a replacement, but perhaps one will arrive before On Air joins the Google Graveyard.
- YouTube Help