Right, so it's a chromium C++ repo that you need to create bindings for to interact with. I have no doubt that an organization like Discord has the engineering resources to either write their own bindings to WebRTC or to roll their own implementation of the components, but if I'm a an individual developer that wants to interact with WebRTC without a browser, then it's pretty difficult.
One common desired use case is using WebRTC for p2p torrent communications. Right now the best way to do this is in browser, or to use an Electron app that can bridge the WebRTC clients with the standard desktop torrent clients.