You mean: "In 2001 we reinvented XP/Agile because we couldn't be bothered to read the old literature to see if somebody else had done something like that before" ?
Really many of ideas which we've come to associate with "Agile"-like methods only really started to become codified about the end of the 1980's in more traditional manufacturing. I don't think it's too surprising that it's taken the software industry another 10 years for this stuff to become mainstream.
Also from your other comment above...
> Ever looked into how USA put a man on the moon ?
I'm sure FreeBSD would be a lot better if you gave it $25 billion USD over 11 years as well.
It takes more than just good will and intelligent people to produce high quality results.
UNIX was originally written as pair-programming.
Brooks refers to agile in The Mythical Man-Month (he didn't invent it, check his references)
You are being overly optimistic about the pace of human cultural development. The rest of the world is only just starting to realise again that perhaps we have cultural issues that lead to low quality results. Bell Labs have numerous advantages over the rest of the world when it came to fostering the sort of culture that produces high quality results. Just reading the history books really isn't enough for that to come about.
TLDR; I blame Windows ME on World War 1.
From http://www.drdobbs.com/open-source/interview-with-ken-thomps... :
KT: I did the first of two or three versions of UNIX all alone.
Later, he emphasizes that they didn't even look at each others' code:
DDJ: Was there any concept of looking at each other's code or doing code reviews?
KT: [Shaking head] We were all pretty good coders.
I remembering reading somewhere (Dennis Ritchie's C History article?) that once they both programmed a solution without consulting each other, and later when they read it, the solution was exactly the same, even down to the variables' name.
Power of C? Two people who thought alike?
>>KT: [Shaking head] We were all pretty good coders.
Which the modern world doesn't have enough of. Demand is so high that quality of supply doesn't matter, just enough to satiate the demand; which is in stark contrast to the early days, when computer science was a research field only privy to scientists and later to hackers and crackers. When it went mainstream, and grew to an industry, its no wonder that it acquired all that which comes with it.
see: Tom Gilb Principles of Software Engineering Management (1988)
We do have an awful tendancy to reinvent the wheel, but I think that building Cathedrals vs building Bazaars is the wrong metaphor - I prefer building simple vs building complicated.
The "bad" people PHK describe are building complicated. The "good" people build as simple as possible, but no simpler.
edit: 1992. Only been building bungalows.