yt-dlp is not dependent on youtube-dl. yt-dlp is simply a fork of youtube-dl that happened some years ago due to the maintainer of youtube-dl refusing any updates that would break compatibility with python 2. yt-dlp has since been the most active youtube downloader repo on github with pretty much daily commits and instant fixes when changes to youtube happen.

> yt-dlp uses youtube-dl as a core, so if something breaks still needs to go to the youtube-dl and fix it.

No, they don't. yt-dlp is a fork - if something break, they can just fix it in their own codebase without needing to go through yt-dl. yt-dl is still somewhat active, but almost all their commits are backports of fixes from yt-dlp[0].

[0]: https://github.com/ytdl-org/youtube-dl/commits/master/