I would love to host an ultra high quality stream on my own web server, and then have that exact stream piped to YouTube live via OBS. Is there an easy way to do that now?

YouTube likely won't support streaming 3440x1440 60FPS video, and while discord technically supports it, they usually compress the footage fairly aggressively once it's sent up to the client, so I'd like to host my own; it only needs to support a few people. I wouldn't mind hosting it so my friends and side project partners can watch me code and play games in high quality.

I would send your high quality stream to something like Broadcast Box with Simulcast enabled.

Then you can forward your lowest quality stream to YouTube with FFmpeg/GStreamer. Hopefully no re-encoding needed!