On the contrary, libraries are there to facilitate the improvement of said "«modern society»".
Even in terms of cultural trends, librarians have a shared responsibility to guide the public. And they did. These decisions are not made solely based on the least-checked-out books but also on ideological factors - what they think is good for the public.
To my larger point, you cannot expect me to shed tears over publishers harming your ability to lend books because of your status as the sacred gatekeeper of public education when you've already abdicated that role. I think there is tremendous public good in free public education. I don't think there is much public good in free public entertainment.
Some things where both written to be high brow and ended up being remembered but that has more to do with quality than their intended audience.
Do you know what belongs in libraries. Books, newspaper, interactive media, movies. The knowledge, writings, and creation of human culture. Humans are not machines. We need both knowledge and entertainment to survive and thrive.
Publishers would lock up society and culture and charge you to use it. Fuck them.
https://en.wikipedia.org/wiki/Public_libraries_in_North_Amer...
As you can see, libraries in the US were founded to advance 'learning' and 'piety'.
Here is the treatise of one of the biggest influencers and advocates for the creation of the public library system.
https://ia600909.us.archive.org/10/items/intellectualtorc00t...
I strongly encourage reading all the citations in the Wikipedia article surrounding the creation of the library system. Sadly, many of them are paywalled and inaccessible via even the Archive project, Google Books [ed - to be clear if you think I am pro-publisher, you are wrong: the former two projects had more potential to do good than I can express], and likely your local library. But you can find enough to prove the point.
There has been a massive shift in the mission of libraries in the past several decades, and the public didn't get a say.
The mass destruction of older books and classics is easy to observe by searching your own library catalogue. I provided some sources and one commenter even provided a link where librarians justify the need to destroy books using outdated or biased language.
I agree that public consumption has been trending anti-intellectual but I don't see how libraries are to blame. Your ire should be directed at modern society. Unfortunately that's a rather broad and manifold thing to dissect to determine where the problems lie.