"Libraries" is a great example of cult lingo that makes no sense

Library was already a word before that had no meaning related to what these things are

You could call them collections or exhibits or something if you wanted a metaphor along the same lines that actually makes sense

But you go along with cult lingo because you like the cult (and the money printers that cult has gotten pretty strong access to in modern society, much like some of the other big cults people use senseless lingo to feel like part of)