[dredmorbius]

My principle use of youtube-dl is through other tools for multimedia playback, most typically mpv, mps-youtube, and other command-line media playback --- video rarely interests me, and the ability to throw randfom URLs at mpv and have it find and play the appropriate media files (sometimes YouTube, Twitter URLs w/media (https://toot.cat/@dredmorbius/104565986372976258), often podcasts, other video hosting sites, Soundcloud, etc.), is quite the win.

In mpsyt I can curate search and lists for playback (painful or impossible with the Youtube Web client), mpv can take files with lists of URLs to play. Both use youtube-dl for media access

Very often audio-only for headless/background playback.

Also for offline playback when not on WiFi or hardline LAN link.

There's also considerable processing and metadata tools available, including grabbing transcripts from YouTube videos.

The Swiss Army knife metaphor is quite apt.