Good mate of mine is in the force (Wythenshawe). He was first on scene a few years back when his Sergeant got it in the face from the bloke with the Samurai sword.
He has a different view. And again, the crux is that I don't think anyone can judge a situation from 20 seconds of video on Twitter.
I've never been a cop. I have been subject to quote a rigorous working over when I was being a mouthy twat. It hurt. I think it might have been excessive. Boo hoo. I got over it. And should have not been acting in the manner in which I did.
Anyway. I don't really care other than being bored on a Sunday and I'm happy to consider this in the frame of your expertise.