rstp-simple-server is fantastic, I use it for all kinds of stuff and appreciate how easy it is to deploy. More software should eschew having a million dependencies and focus on doing one thing WELL :)
IP cameras generally stream through the Real time Streaming Protocol (RTSP). This cannot be directly played in the web and also requires authentication in most cases.
MediaMTX acts as a proxy to convert RTSP→WebRTC and take care of the authentication.