And hence the coding quality separation of gstreamer plugins. There is a reason the plugin ended up in gstreamer-plugins-bad, and most of them it is due to code quality or lack of maintainers or both.
EDIT it's both: https://gstreamer.freedesktop.org/documentation/splitup.html , http://askubuntu.com/questions/468875/plugins-ugly-and-bad
The issue here is that distributions should offer more granularity with on demand codec installation. Does it make sense that to play an mp3 (not that sure this is the case) I get also the NSF decoder?