A bit diversionary from the main problem here - which is humanity on a downward spiral - but the cabin crew, if the caption is correct said "don't take video please", which seems closer to a "polite request" than an order.
I guess from the crew point of view, it's a no win situation. I don't handle aggressive people, nor have I been trained to, but it may be that stopping someone filming is in some kind of comfort zone, whereas confronting the situation was likely to lead to conflict and out of the comfort zone - so it could be a subconscious decision to go with what you are familiar with to buy time. I don't know how the brain works and I won't criticise the crew action as I wasn't there and I doubt I would be able to handle it myself.
It is a shame that there isn't more video though, even to allow a crew post mortem of the events and to use for future training.