Okay, this is funny, but as for people suggesting that it should actually exist? Sorry, but that is not a good idea. Aside from the fact that, (as shown at the end of the video) this would be all kinds of illegal, it would be far to subject to interpretation.
Not every asshole exorcises their pettiness by being rude or violent, lots of them exorcise it by being deceptive and manipulative. Giving power to the majority does not ensure justice, it only ensures ostracism, justified or not.
Weather someone is deserving of being punched in the face is entirely subjective; people could be tagged just because someone else was being petty or unreasonable.
Say you have a coworker who constantly plays loud music on their work PC while everyone else is trying to work; you report them to a superior and they are reprimanded. Your coworker tags you because they are too inconsiderate to accept that they were at fault.
Say you have a kid who is harassed in school for something beyond their control, such as their appearance. At one point, they stand up to one of their harassers by yelling or cursing at them. The kid who was being harassed is tagged because the other children are more concerned with being popular than being ethical.
The moral of the story; lots of people agreeing on something doesn't make it just or accurate.