I don't think these kinds of lists are necessarily always true, or always relevant, but I think they are great at provoking thought, and great at reminding us that real life is impossible to cleanly codify into a computer model.
It's also important to remind people to not roll your own when battle-tested libraries exist.
(The exception being, of course, building something for the sake of learning. By all means, build your own date formatting functions, but don't put them in production.)
Assuming that the library exactly serves the needs of the project without much cruft, or the cost of rolling your own is higher than using a library all else considered, and the library is well written and documented, then I agree.
As a completely unrelated aside, I wonder if there should be a "Falsehoods programmers believe about libraries"
I'd certainly like to see "Falsehoods programmers believe about passwords". And for that matter, "Falsehoods programmers believe about programming", and possibly "Falsehoods programmers believe about falsehoods". ;)
I don't think these kinds of lists are necessarily always true, or always relevant, but I think they are great at provoking thought, and great at reminding us that real life is impossible to cleanly codify into a computer model.