Thankfully I don't see much of this in the media any longer. But it is a question I have asked many elsewhere while it grabbed media attention. I consider it very serious. This " fun " can change lives in a second and not just for the puncher and the victim.
So, how would you respond? Disturbing video if only for the reason this was not a mutually agreed fight or any prior indications attack was imminent, ie a guy in your face. You may choose not to watch it. Innocent people minding their business getting slammed out of the blue for nothing they provoked. Some people have died as a result of this game.
https://www.youtube.com/watch?v=2U-Z1fZ9F3s