ironic that winamp is was built on open formats and widespread IP theft (music ripped and shared)..... but they're strangely prickly when it comes to their code.
The guy who wrote Winamp Sold it decades ago. So you should clarify who is defensive about their code :-)
The original coder is really good - he also wrote the awesome AVS visualization plugin for Winamp which among other things utilizes a special programming language called "eel".
After selling Winamp he went on to create Reaper which also uses eel I think.