> There is plenty of information available today Last time I looked today, we were not in a post civilisation world. This information will be gone. How is information going to survive an event that wipes out 99% of humanity? No power no rule of law. The sole concern of the remaining people is to get food and get to an environment they can eek out an existence. The information of today will be all but gone.

> I have a friend who has for decades run his own little metal furnaces. By comparison to the modern industrial refining processes, his are primitive. But they are easily built and work well for the individual.

Sure, but how many people have this knowledge now? How many people will be left with this knowledge after:

a) the event itself b) after years of struggling to survive and finally being able to more than subsist

First priority food and shelter. Food, you can scavenge supermarkets, but eventually it will run out. You will need to grow your food by hand. You will need to find seed and be successful otherwise it is hunter gatherer lifestyle, with assumed hunting is minimal as whatever wiped out 99% of humanity did the same to other animal species.

But lets say you found a good piece of land where you could survive, it would take years. Lets suppose you were one of the few people who knew how to build a furnace. Are you going to leave your patch of land to go wondering in the remnants of what was left of the city to get some scrap metal to carry back? I don't see it happening. Then in a generation of what was was is forgotton