I think the argument there was that lots of things were so much easier to do in Lisp that people wrote their own implementation, then they thought "what's the b

I think the argument there was that lots of things were so much easier to do in Lisp that people wrote their own implementation, then they thought "what's the big deal about it?", and then they didn't share their library because they didn't think they've accomplished something meaningful to share. So you end up with people doing things in C++ and Java and publishing it and getting their code reused because 1) the authors of the code were more likely to think of publishing their code as a useful thing, and 2) due to some things being harder in those languages, other people were more likely to shop for libraries rather than to think "I can do this myself".