I don’t think a fork will solve anything. I’m pretty sure the reason they did this is to cover their asses (don’t forget that it was very near to being taken down just a few years ago).

Further, yt-dlp has implemented plugin support, for this exact reason. I think that’s a new feature compared to youtube-dl. You can add your own extractors as plugins, wherever you find them. As I remember there are a few plugins that are even maintained by a yt-dlp maintainer.