Crazy Fucking Videos

You (in that instance in your 20s) weren't a cop on duty I assume (horrible situation tho). Neither was the bouncer. You were just four people that should present your testimony to the court.

If I go, finger a cop (non-consensually), & then step back, they still are not allowed, under no circumstances, to punch me in the face if I'm not an active threat. That is just literally the law. The excuse for the punching would be anything other than a direct consequence (bcs we do not have retaliation enshrined in law, bcs "civilised" and whatnot). They would be guilty of punching (and me guilty of fingering).
(Morally justified on their part & unimaginably horrendous on my part - just to be ultra clear.)

Would the face-punching be justified?
Absolutely (and much, much more).

Would it be legal?
No.

"Eye for an eye" is not an anarchistic mandate, it's a procedural event where a third party decides on face-punch distribution ("legally").
(Not that I'm saying what op posted falls under that, that is just sadistic tendencies being allowed en masse for political goals. It's too well documented & officially commented by govs in question to be overall misunderstood as anything but that.)

Nobody is saying context doesn't matter.
The argument is that for a law enforcement/cop to "legally punch" someone there is all the context necessary already present in the vid - the person was standing there.
Folk will ask for additional context on vids of cops punching (and even killing) someone handcuffed on the ground. Sure there is context, from breakfast food to horoscope. Still legally not allowed to punch.

If a cop catches me speeding they don't decide between (the illegal option of) two face-punches or a (legal option of a) monetary fine.

Solving violence with violence is what we seek to avoid when we want to advance civilisation.
(Again, the OPs vids imho shows only violence, not even 'violence hoping to solve anything'.)