If you were the OP and read that without knowing you might just give up. That is what I am talking about. I guess that is just the internet though. I've seen it more and more here in the last few years though. Gotta wonder what "knowledge" is going to look like in another decade.
I agree, and that's why it's good that someone can contradict a wrong opinion (or assumption).
As for what knowledge will be: many assume that the internet will eventually be the repository of human knowledge, where the true answer to any question can be found instantaneously. Perhaps that is somewhat accurate. However, as seen in threads like this one, the internet doesn't fare so well with esoteric knowledge. An incorrect opinion can stand uncontested for a very long time about a subject where few count as authorities. That is a situation which will only get worse.
Ferrotyping is a good example of a different type of specialized knowledge. A great many people knew how to do it and could easily answer the question posed by this thread. But all of those people stopped doing it, never bothered to write down anything about it, and moved on. They're not here.