The Few. The Proud. The Geeks.
LOL! I also have a slide rule.
In my case, it is plural slides rules. And that is what I used hard for 4 years at University and then 5 in the Military. When I went into the Marines, 4 function calculators were about $1,000. When I got out, you could buy a full function Scientific Calculator for $30. But the two environments in which I worked, field surgical suites and military helicopters, both prohibited any electronics in the interior at that time. And I was wicked quick with a slip stick, so I ran all the drug dosage numbers for a MAST unit and a SAR unit for 5 years. And when the wrong dosage of IV Potassium can kill, you don't screw up. So I do think of my ability to do serious engineering completely free of electronics a decent survival skill. Even today, no matter how complex the problem, I do first order approximations on everything to make sure no one has gotten the right answer off by a decimal point (or several of them). I am about triple Malcom Galdwell's mastery level of 10,000 hours with pre-electronic era math tools.
I do have 30 days of freeze dried food and 30 days of water. But I have only enough medical supplies to do one small surgery or a couple broken bones. True self sufficiency is way out of reach as a practical matter IMO. If there is a serious long term shutdown, I doubt I would survive long without a bit of luck. I will be 70 years old in a few years; at some point one realizes that hard survival is as much physical as mental. I totally acknowledge that the most important survival tools is between one's right and left ears. But one must also have the physical stamina, good vision and overall good health required to deal with a much tougher and likely more dangerous life.
If I were to survive in a long term shutdown, I am pretty sure it would be based on my engineering skills and tools. I have the aforementioned slide rules, several sets of old school math tables (they cover everything), a couple of copies of the CRC Handbook of Chemistry and Physics as well as a decent reference set for pre-industrial drugs. I have a small, but well covered cache of seeds for everything from congestive heart failure to diabetes (and while the dosages are a problem, powered Foxglove and French Lilac, as well as the other 20 types of plant seeds I have, really do work with high efficacy.) All the seeds are in a big inert jar full of Nitrogen gas.
If all this seems kooky, well to each their own. I have invested the least amount of effort and resource for the maximal yield and the lowest footprint. Very long term storage and ultra low maintenance is part of my SHTF model. Everything I own for such an eventuality fits comfortably in a few mid sized boxes.
As for ammunition stockpiling, yeah I have a few thousand rounds. But think of the statistics of the matter. Other than hunting for game (which would be a joke anywhere I live), if one thinks they are stockpiling ammo for dozens or hundreds of actual firefights, think again. The average well-trained soldier gets wounded or killed within the first 5 enemy engagements. Yes modern stats are better, but only with all the electronic support and mechanized armaments. One would have to be the very quick or the very dead if there are lots of firefights in one's future. My best option is to be perceived as too valuable alive (engineering and field medicine) to be out on patrol.
My wife is a jeweler with cool tools - many of them non electric. Just for fun, I got the specs and schematics for a few simple surgical instruments. She was able to make serviceable models of 3 instruments in a long weekend. We would make a good team in a bad future, but we would need a strong community that wanted our skills and resources.
So put me in the very cautious camp of "a bad future is certainly possible, and I am prepared a bit, but I hope to hell nothing like that ever happens."