I don't think anyone has really argued the lethality of the .22 long rifle. But the argument is if it would be quick enough to be "effective" in a life or death fight. As a "survival round/weapon" I am not sure if there is a better choice. A person can carry 2000 rounds of .22 for almost the same weight as 300 rounds of .223. It's quiet, lethal, cheap, and until recently, as common as dirt. And to add onto all of the pluses, it is incredibly accurate.
As far as putting big game meat on the table? Shot placement, shot placement, shot placement.....
It will get it done.
Frank