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.
It still leaves you writing in c++, but it lets you build a self contained server without any browser stuff. There also were java bindings which is what I used when I was experimenting with it. You just have to build your .so and .jar files.
EDIT: Here's some scala code that I wrote that uses the native bindings. (Please forgive the messy test project that I have abandoned).
https://github.com/jgrowl/livehq/blob/master/media/src/main/...
Or do you want something that has a completely different API? It would be nice to be able to ignore the JS idioms, but it is tough to start from scratch.
There are many aspirational repos that have been started over the years with the intention to implement WebRTC but very few of them actually made good progress.
I too would love more third-party language-native implementations. Right now everyone is binding to the C++ codebase.
The real problem without having language-native implementation is that it creates a protocol rift. Things like BitTorrent vs WebTorrent, or IPFS native vs IPFS JS: It's effectively UDP/TCP vs WebRTC, clients on one end (native apps that aren't NodeJS) can't speak to clients on the other end (browsers) without a relay bridge (which is always NodeJS).