It is, but I don't think in this context.But the legal advice I got earlier in this thread is that proportionality isn't a thing. Strange.
If the aggressor displayed a knife on the other side of the street and the shooter shot him then, you could argue proportionality and many other things, but fact is, that is not what happened.
How in danger does one have to be to be able to defend yourself? Surely a stranger barging across flowing traffic to wrap his hands around your throat meets that standard, does it not?
Were the hands around the throat a greeting I'm not aware of in some other culture?