In the video he says he's a professional turner of 30 years and that he spent 6 hours the previous day trying to work out why you shouldn't use the Spindle Roughing Gouge on bowls and faceplate work. He notes that the accident was not intended.
Whether or not he's right in showing what not to do, and why you shouldn't, is not the point. When you consider his experience and what happened to him, in his demonstration, inexpert turners are at even greater risk of injuring themselves.
Then you consider how many YouTube videos of turning [I've seen] employing the SRG to work faceplate's etc., all of which are watched by enthusiastic beginners (read the comments) who have little or no other tuition, and you start to realise that this one voice in the YouTube e-world is trying to do the right thing.
He posted this as a serious 'Do not do' not 'look, I'm a bloody idiot!'