In a catastrophic situation, you have two options: hunker down, or walk out (never drive). Staying put means that you can stockpile a few weeks worth of food and water.
Walking out means that you might eventually get to a place not affected, but it requires a lot more preparation. Have cash, food + water for a few days, two flashlights, first aid kit, compass, paper maps in ziploc bags, a knife, axe, portable stove, pot, fork, spoon, nylon cord, poncho, polar fleece, spare leather shoes, socks, warm hat, multiple redundant sources of fire, and possibly some luxuries like a tarp if you can handle the weight (but better not to). And know something about survival in the woods.
You take your chances either way.
I understand what you are saying, but I'm going to make a guess here... you have never served in the military, have you? There is a whole subset of the population(veterans) around you, who had (from the article) smoke signals, hand signals, and morse code drilled into our heads. We may be rusty, but it's like riding a bike. It might not be as nifty as making a fire by rubbing 2 sticks together, but a couple of us each with a piece of broken glass can communicate miles away by signal flashing morse code.
Also, the article was about communicating. Your reply seems to be more about self-preservation during an emergency. There is some overlap in those 2 domains, but they are not the same.
No one understands AM/FM radio, NOAA weather radios, CB radio, walkie talkies, or ham radio?
Search and rescue pilots do not understand the body signals and ground symbols given in the FAA's Aeronautical Information Manual (also part of the Convention on International Civil Aviation), which should be studied as part of basic pilot training?
A bit of Googling turns up that three or six regularly spaced flashes of light, blasts from an airhorn, tweets on a whistle, gunshots, etc., is an internationally recognized distress signal in mountain regions, and seems to be well known among the relevant populations.
86% of all people age 15 and above in the world can read, so finding someone who can understand a physical message board should not be a problem. Physical message boards are in fact often used in disaster situations when other communications is down.
If you're going to prep all of this stuff so you have options in case of an emergency:
> Have cash, food + water for a few days, two flashlights, first aid kit, compass, paper maps in ziploc bags, a knife, axe, portable stove, pot, fork, spoon, nylon cord, poncho, polar fleece, spare leather shoes, socks, warm hat, multiple redundant sources of fire, and possibly some luxuries like a tarp if you can handle the weight (but better not to).
it's probably better to prepare a bike (gravel or cyclocross for best flexibility and efficiency) as well so you can get to where you want to go 5-10x faster. You just have to wait a day until everyone has run out of gas so you can take the highway.
I'd also add a couple of emergency blankets for cold and hot weather, plus a foam mat to isolate your body from the floor. I'd drop the fork in favor of makeshift chopsticks, and/or cut the spoon into a spork. Wool for everything textile you wear.
And visual code (ship signalling by light) is totally different from code sent over radio. Also, no one uses Morse Code anymore for anything meaningful. Ham radio hobbyist use it for radio contest, and occasional rag chewing, but the most meaningful code you'll hear today are repeaters or vessels identifying... this is callsign... but that's about it.
Great hobby and very simple way to communicate but not worth it for survival IMO. And I know Morse Code (and can use it when I have to) upto about 15 to 20 WPM. I am rusty though as I seldom have a need or desire to use it.
I was surprised last night to learn my wife doesn't know how to signal SOS in Morse. Granted I was a boy scout for a few years, but I thought this was something everyone was taught. It's a sham that is apparently not the case.
if you're on a boat all day with a ham radio or such devices, sure it's useful to know. but in a big city or urban area with no general access to such devices? are you going to write dashes and dots on the wall???
not saying that it's useless to know. i learnt a lot of these things from my parents, and i would teach my children if i had any, but i can totally relate to people not caring about it in my area and finding it some niche interest for 'nerds' or so.
Even if the people searching the rubble don't know SOS, they will still recognize that it's not a natural noise.
Is there any truth to this? There's a bunch of obvious technical errors (surviving nuclear war was never a design goal of the Internet, backbones have been fiber-optic since 1987, not clear why ethernet cables are supposed to be less reliable than telephone cables). Wireless is of course easier to interrupt than wired, but in most places last-mile links are still hardlines.
The real issue is that you need power and a functioning service provider, but that's always been true.