JWPlayer isn't needed to view the streams, but it is what is used on the html pages that people will be directed to.
https://github.com/timvideos/streaming-system/issues/60 JWPlayer is released under a CC BY-NC-SA 3.0 -- the NC (non-commercial) part means it doesn't satisfy the Debian Free Software Guidelines (DFSG) and hence is not truely "free (libre) software".
If someone wants to swap in something better, now is the time.