I have been quite happy with some of my SFU code on top of the Rust wrapper for Mediasoup[0] which I understand from this post doesn't have congestion control. I would love to give this a try, but I fear including a library w/ AGPL license. The license choice is not worth hashing out here, and I'm sure Signal's goal isn't necessarily developer adoption compared to openness, but it will hurt adoption.
0 - https://docs.rs/mediasoup/latest/mediasoup/