I used to use “the STL” to refer to “the part of the C++ Standard Library strongly influenced by the design of the historical library”, excluding iostreams etc. Later, I decided this didn’t really achieve anything. It’s a Standard Library that’s full of Templates! There are other design philosophies in there, but they are increasingly unimportant. Having to say “C++ Standard Library” all the time, or trying to popularize a new acronym, are worse alternatives.

Yes, effective communication is valuable. I have been working on this library for over a decade and I find that the short, memorable acronym ultimately makes it easier to talk about the thing.

That said, we are primarily using the acronym for the repo URL and the directory structure; the readme makes it clear that this is “also known as” the STL.