At this point wouldn't it make sense to just rewrite it from scratch? I'm sure there are projects already doing this (take a look at this one for example! https://webamp.org/)
I mean again, I'm currently using Audacious, which even supports Winamp 2 skins, so it's pretty much the same aesthetically. And it works well enough for my workflow (which is that I rarely ever actually look at my media player--I just want to queue something to play and have it run it my system tray, with Play/Pause available through MPRIS or media keys).