I am reaching my 40's and back on the university we had lots of books and papers since the early days of computing. Given my interest in compiler development, I just devoured everything I could get my hands on.
So although I started coding around 1986, I managed to get hold of lots of information.
How do you run a Lisp Machine environment today? Or Oberon System 3 or v4 (I never tried anything later)?
It is easy to reinvent and re-sell stuff when everything before is pretty much no longer available.
I've had a few conversations lately with people who worked on some of this stuff. A lot of history is totally gone.