tl;dr: Author advocates archiving YouTube videos locally since content regularly disappears, recommending yt-dlp (or wrappers) plus bulk storage as sufficient for most users. For their own overkill setup—needed to play hundreds of Let's Play videos via Jellyfin—they use ytdl-sub to preserve playlist structure (mapping playlists to "seasons" in TV Show libraries) and Tdarr to re-encode files to HEVC, saving ~700GB on a 2TB library. Tdarr is grudgingly recommended only for the desperate, given its clunky UI.