A meme ask almost prompted me to give this long tangential answer, but I had the presence of mind to refrain from that and put it here instead:

On the topic of offbeat ideas about Numenorean society, and by extension, an offbeat but by no means unheard-of idea about society in earlier Arda in general, I headcanon thus: Numenor was the first society to invent real libraries! Especially, public lending libraries.

In the real world, the history of libraries and library loans is long and complicated. But Arda sure as hell bears little resemblance to real life history - which is kind of the whole point of the setting being Arda! Alternate and convergent explanations for history and the present day, with each one resting on wildly different constructions of reality. See, in Arda, my headcanon is that all throughout the Years of the Trees and the First Age, libraries of any sort weren’t really a thing, and even written lore wasn’t really much of a thing. Dwarves in the First Age didn’t let most non-dwarves come into their halls, and also wrote a huge proportion of their lore in non-mobile stone engravings - the walls of their cave cities, steles - and in systems of non-text semiotics via their craftwork. Elves both of ME and Aman were largely oral societies and writing was kind of, extra, either for small-potatoes practical communication or for really fancy stuff (this is just fun extrapolation given the immortals-with-perfect-memory thing). And so were the Edain for the most part (I think this is more canon, as a big part of the history of humankind in Arda is that the ancestors of the edain abruptly stopped passing down a certain cluster of oral traditions shortly before they came to Beleriand, which left the later humans with significant gaping holes in their history regarding the Fall etc).

Until, of course, the speeded-up clusterfuck of wars and mass death starting with the Bragollach.  As the whole Beleriand debacle sped up through the Nirnaeth and the kinslayings and on into the War of Wrath, people began frantically writing stuff down and keeping haphazard hoards of it here and there, Nargothrond and Gondolin, Doriath and, especially, Sirion (Dirhavel was a BIG proponent of this due to having a deep appreciation for the idea of information being lost via death, which is why the Narn i Hin Hurin has so much more internal consistency than the Quenta Silmarillion whose writing was....lets say not nearly as well-organized, and Elwing and by extension the bb!twins were mad for Dirhavel.) And then carting anything that survived off into Ossiriand after/during the War of Wrath. SO. Very little written lore at all before this time.

In the early Second Age, of course there would be a huge amount of work in Middle Earth among the groups who migrated from Beleriand, to get peoples’ knowledge gathered up, written down, etc. But there’s lots of immortal elves, lots of oral tradition, lots of unconnected disparate populations, etc, and also ME is kind of a disaster zone due to the aforementioned continent-destroying war. Low resources, low organization, lots of problems and probably violence to juggle, high strife, high scatter, high danger. Plus, there is still plenty of conflict and enemy populations, to make security and barriers to access important to keeping precious records safe. So just gathering and compiling all the lore, or writing it down in the first place, would be the big challenge in ME.

But Numenor! Numenor, otoh, is a peaceful island paradise with almost no danger and more resources than anyone needs, with a single pretty unified human population under a single king’s rule. The people born there live a very long time, the men don’t need to do any fighting, children are few per family, the childbirth and child-rearing period takes up only a small fraction of womens’ lifetimes, and everyone has a whole ton of free time after the first stage of building and establishing communities and cities is done. Plus they’re friends with Tol Eressëa. This is when the second-generation Numenoreans decide to do a huge push to get an army of scholars and librarians to get everything written down, organized, catalogued, and made accessible to everyone, since humans, unlike elves, can’t just live forever and remember everything they’ve heard, and need to work as a relay race, maintaining and building on the work of their predecessors in order for information to remain intact. And given how much time and wealth just about everyone has and how good life is for the whole population, it’s actually logistically feasible (even without (before? Numenor is firmly ahistorical) the printing press) to make multiple copies of many tomes of various types of lore and just let people borrow them whenever without a big security deposit beforehand - just return them in a set time okay!

Of course this was all restricted later on when control of information became super important in order to control a population through control of the narrative of the Numenoreans’ history, but well, at least the concept caught on elsewhere!

By which I mean, of course Elros personally decided to make them, and of course Elrond deliberately ripped him off in Rivendell much later. What else did you expect from me, man.