I'm glad my project caught your interest. But, no, it isn't a "Ring <-> WebRTC bridge", more of a "Ring <-> Node.js bridge" really.
Despite Electron being a stripped down web browser, I am not using the browser's WebRTC API to provide Ring functionality. Instead, in the first few weeks, I wrote a Node.js wrapper over the actual C++ Ring Daemon. This wrapper was not a WebRTC (or any network protocol) based one, it is a Node Native Addon . These Native Addons can be imported and used in any Node.js projects (which Electron apps are).
This Node.js module is generally useful (use it in any Node.js project as you like) and not at all focused on a trendy, perhaps transient toolkit. I've tried to keep the Node.js wrapper easily reusable and with as little coupling as I can (of course, it is a work-in-progress).
The reason we're focusing on an Electron client is the ease and speed of development it will provide to anyone contributing. Right now, when the Ring team wants to roll out an update they have to implement it for each platform's client (Gnome, OSX, Windows etc.) separately. This has even lead to some clients being left behind in features at times. A unified Electron client that runs on all platforms will make better use of the developer's time. A very obvious example is that writing UI in HTML/CSS etc is much more faster and easier than in, say, Qt. That time can be spent elsewhere.
I hope that clarifies my project.