Ok, so let's enumerate those concepts, stick 'em up as a guide for future generations (probably a good idea to work out what they are ourselves)

1. Code is data, data is code

   Implications: everything should be a first class citizen of the language, able to be passed by reference, altered by functions elsewhere.  

   Examples: s-expression in lisp? Subclassing built-in types of oo language (python new style objects)

2. Configs are applied to code, so that the same code can run unchanged on dev beta and live. (this is my favourite reinvented wheel du jour - devops.  In fact the whole 12factor app recently on HN is a great example of rediscovered wheels - or perhaps more fairly a great example of doing this guide to future generations too)

3. iPads are no way to type into unresizeable text boxes

... Edits coming when I get a keyboard

Let's say you wrote that list, now in 2012. In 2015, people will look at the date on the blog posting and immediately disregard it because it's "old". That is the problem. The knowledge hasn't been lost, over the last 30, 40, however many years. It is being actively shunned by people who take all the complexity involved in a useful system utterly for granted and think they don't need experience or to study the experiences of others.

I find it fascinating, it's as if kids these days believe that their fathers had all the things they take for granted, like smartphones, tablets, AJAX, whatever, and then, because they were stupid, chose to use green screens and FORTRAN instead.

I think why we disregard old material is because we were bitten by that while we were learning programming in the first place. The web is full of old cruft that no longer applies, and some of it flat out dangerous, so we shun older information in favor of newer information.

Haha, you are proving my point "the web" indeed, this problem has been going on for long before there was "the web", tho' the web has certainly made it worse, everyone thinks they're using the latest greatest thing, they don't even realize that it's just yesterday's leftovers with different buzzwords attached. That's the tragedy here. And who is to say the new information is any better? At it's very best, it's just repeating what has gone before. Why not go to the original, and learn for yourself?

Who is people and how do you know they do that? I don't think people do that. I feel like Hanlon's razor applies here.

The constant re-inventing of the wheel is the proof. The state-of-the-art hasn't really advanced in 25 years.