The example usage for the network stream option writes "yourtube.com" instead of "youtube.com" (notice the 'r'). The exact line is here:
https://github.com/videolan/vlc/blob/721c216bf8faaf2205aacf744ab20b1c5e3ec82f/modules/gui/qt/ui/open_net.ui#L47
If you choose to fix this typo, I would also change "http://" to "https://" in the URL.