That is true but sometimes survival is mesured in hours and days not all out end of time .
True. If history is any indicator, the first few days or weeks (depending) are pretty chaotic. Lots of killing going on, people panicked about the future, communities or gangs will form up for protection. Large game will be shot to hell by folks who have never done it before, including domestic animals and pets. The elderly and the invalid might not make it very long. All the bodies attract disease and vermin. Surviving that I would argue would require something a bit larger than a .22 as there will be a lot of those hours and days.
Lot of migration going on, so folks in the country set up to ride it out can count on waves of refugees wandering on their property. If you live within the range of an SUV on a full tank of gas from city limits, that means you. First wave immediately after, and they'll probably be in shock and relatively kind. All the waves after that will be desperate and willing to fight. Migration will stop eventually, except for the random little parties on foot. Something larger than a .22 at your country home would seem to be useful for that too.
But then it will settle down; folks will get a feeling like, we made it! and the task of surviving the long term will settle in. In the absence of established law & order, country justice will be the norm, probably conducted by the heads of households within your community taking leadership. Something larger than a .22 might be nice to have during those days, but probably not used as much. A plow and a mule would be worth more.
However, all along the way there will be LOTS of barely fired dropped once ARs and AKs, 1911s and Glocks for you to collect and store. Why those? Well I am modeling after events that have occurred numerous times on other continents, and folks who can afford the higher end weapons normally don't match the profile of a survivor. In our country, lots of semis get sold in cities. $1500 for an AR, $900 for a 1911, to shoot at the club on weekends with your friends from the tech support division. Transferring that power and capacity into a survival model is hard for most, so while they have great tools, they lack the ability to leverage them for survival. On the other hand, a country boy who has taken game before with his 30-30 that's been passed down 3 generations, knows the value of a single shot, has taken life, and by nature of his status in society, is more likely to posses a survivors mentality. In other countries, its the guy with a bow or a .22 who is still eating when the civil war dies down. I've been to post-civil war arms markets, and there are a lot of nice fresh AKs and CZs in stacks.
If you could only grab one, and .22 was it, you're probably opting to not engage with anyone for months probably, stay below the radar, and leave a light footprint.