But YouTube is the only one that yt-dlp uses Deno for. No other website on yt-dlp's list has put up enough of a fight to merit an external JS runtime; only YouTube.
From the September announcement:
> The JavaScript runtime requirement will only apply to downloading from YouTube. yt-dlp can still be used without it on the other ~thousand sites it supports
yt-dlp supports a huge list of websites other than youtube