mpv's bonus is convenience, and the fact that it will seamlessly play much of what you throw at it, whether that's local files, network resources, web sites, etc. Much of that majyck is in fact ytdl/yt-download, but having a standard interface is quite handy.
And yes, I've run into streams that need mixing, which ytdl/yt-download can handle; you point it at both the video and audio sources, typically. (I do this infrequently, thankfully).
mpv's bonus is convenience, and the fact that it will seamlessly play much of what you throw at it, whether that's local files, network resources, web sites, etc. Much of that majyck is in fact ytdl/yt-download, but having a standard interface is quite handy.
And yes, I've run into streams that need mixing, which ytdl/yt-download can handle; you point it at both the video and audio sources, typically. (I do this infrequently, thankfully).