The tricky bit is that you have to get your youtube cookie in order for yt-dlp to get your own liked videos. I expect it to be a lot more LoC to authenticate and get the cookie than to do everything else (which is a one-liner in yt-dlp), so I just do it manually once in a while.

  yt-dlp -f "best[height<=480][fps<=30]"+bestaudio --cookies cookies.txt --download-archive archive.txt --all-subs --embed-subs --embed-metadata --merge-output-format mkv --sponsorblock-mark all -o "%(channel)s/(%(upload_date)s) %(fulltitle)s.%(ext)s" "https://www.youtube.com/watch?list=LL"