It depends on what kind of display. If it were up to me, I wouldn’t put up a display just promoting or celebrating Earth Day, but I would put up a display of books and other materials related to Earth Day, ecology, the health of the planet, etc.
I don’t see the distinction there. In any case, I think part of a library’s mission is to educate, and having Black History Month, Women’s History Month, Pride Month, or Earth Day displays all help accomplish that goal.
How about a Banned Books Display about a book of the holocaust?
It has to be noticed that among the books banned, because of the ones elected to school boards since they were against CRT, was Maus.
These aren’t alternative views or social agendas. These are things that are happening in the Chicago area, or are nationally recognized observances.
The white folk in the neighborhood want the library to pretend that these events and recognized observances aren’t happening at all. They want radio silence about the fact that Chicago is having a Pride Parade, or that February is Black History Month. That is not a neutral stance, it’s an aggressively bigoted stance.
It’s censorship, it’s gatekeeping information about local events and observances because old religious bigots are offended by being reminded certain things exist.
Non-insane is a low bar, so you’re probably right. But, without getting into any other, bigger arguments, I’d say the entirely voluntary aspect of drag story time does make it very difficult to argue that they’re being reasonable. Any parent who objects can simply have their child not attend. Same as they can not allow their kid to check out certain books, watch certain movies, or play certain games.
There are other arguments for why it should be acceptable, but the people against it have trouble clearing this first hurdle.
Library displays, on the other hand, are not announced ahead of time, and could in theory surprise you. So the arguments against them do clear this low hurdle. I’d say that, as is often the case, the issue is one of framing. But I think it would make more sense to put that argument in a separate post.
And, yeah, that’s the framing issue. The OP is framing this as people promoting political agendas. And, yes, if you were talking about pushing actual Democratic or Republican policy stuff, attempting to push people one way or the other, I could agree that maybe it shouldn’t be allowed.
But that’s not what these displays are about. They’re about inclusivity. They’re just acknowledgement that things exist. It’s factual information about history, and promotion of authors with diverse experiences. The only agenda they push is giving people the opportunity to learn about things that exist and they might be interested in. And that is an entirely appropriate agenda for a library.
Those who object aren’t objecting to an actual political ideology being foisted on people. They’re objecting to information being available that they don’t want their kids to read. They want to control what other kids get to read. Their agenda is antithetical to that of a library.
All of the library displays I’ve seen have, in fact, been displays of books on some topic (or books by some category of author, or whatever).

They’re just acknowledgement that things exist.
As I’ve stated above, I was not offended by any displays I saw. (Tho if I had noticed any that were overtly religious, I might have been.) I tend to be pretty oblivious to what is in the display cases, or the “staff recommended” materials. Hell, since I got used to ordering boks on-line and using the drive-up window, I rarely go into the library other than to use the puzzle exchange (a wonderful service iMO).
But is it completely fair to suggest that “things” like Black History Month, Pride Week, or even Earth Day simply “exist” independent of any social or political messaging? My understanding is that such celebrations/recognitions only exist because at some point some interested group successfully lobbied for their recognition.
Personally, I could imagine a library drawing a line saying they present displays for any municipal/county/state/federally recognized holiday or recognition. Of course, I imagine there might be a near endless list of such (often meaningless) recognitions along the lines of “eat pasta week!”
But I also can imagine some folk reasonably asking if that is the sort of “information” they prefer supported by their tax supported libraries. Should there be ANY holiday/recognition celebrations at all?
In case it isn’t clear yet, I’m a terribly strong supporter of libraries/ians. When my kid worked at a number of libraries for several years, I was aghast at the frequency with which assholes (IMO) tried to beat up on librarians to advance their personal agendas - whether re: religion, covid, what have you. But I also realized that my daughter and some of her cow-orkers perceived themselves as social justice warriors, who perceived their jobs as “waking up” the patrons.

All of the library displays I’ve seen have, in fact, been displays of books on some topic (or books by some category of author, or whatever).
That’s what I was going to mention.
I don’t think there’s anything wrong with libraries helping readers broaden their horizons, and I’ve found these displays helpful when I’m selecting reading material from a library or bookstore.
Face it, conservatives just hate education - because educated people tend to not vote for them.

But I also realized that my daughter and some of her cow-orkers perceived themselves as social justice warriors, who perceived their jobs as “waking up” the patrons.
IMHO this sounds like if you would have been fun to have around by the medieval guys that were against the enlightenment that was coming up in those days…
Every time you are thinking about the idea that government should put its fingers on the scales to advance social causes, you should ask yourself if ypu would be okay with that if Donald Trump or some other hated figure gains power and decides to use government functions to move HIS agenda.
The worm always turns, and the power you give to government today may be used against you tomorrow.
Libraries should attempt to provide a wide cross-section of human thought in important areas. Libraries should not be putting their fingers on the scales. They aren’t elected to do so, and they operate woth public money and almost no oversight. No special interests should get preference, even if you think they are doing God’s work. Anything else will just speed up their rush to irrelevance.

But that’s not what these displays are about. They’re about inclusivity. They’re just acknowledgement that things exist.
I don’t know what “these displays” are about, because I haven’t seen them. And I thought we weren’t necessarily talking about any particular displays, but about those sorts of displays in general. So I’ve been considering the set of all possible displays that I could imagine appearing in a public library.

Every time you are thinking about the idea that government should put its fingers on the scales to advance social causes, you should ask yourself if ypu would be okay with that if Donald Trump or some other hated figure gains power and decides to use government functions to move HIS agenda.
This is already happening in multiple states, so I don’t think I need to worry about that in the future. And, I don’t think we should continue to exclude minorities, women, queer folk, etc., from our public spaces just in case some day we’re a fascist state. A library having a Pride Month display is not an atrocity.
I’m so tired of this argument – better not make any noise in case some bigots and brown shirts decide to make louder noises. It’s a ridiculous argument against libraries having a Black History Month display.
Come back and say, “Aha! I was right! Now there a MAGA month and libraries are going to show that! And, next month is Nazi month! Then, KKK month. Told you so!” when that actually happens.
ETA: I just re-read this part:

Every time you are thinking about the idea that government should put its fingers on the scales to advance social causes
That’s a great argument against the civil rights revolution that happened in the US in the sixties. You would be saying the EXACT same thing when someone protested whites-only water fountains.

The worm always turns, and the power you give to government today may be used against you tomorrow.
It does not deny that a worm like Trump is part of the forces of darkness. And so, it will turn on him too, that is a reason why I don’t despair at the thought of the orange worm having a chance of winning.
I think I saw once a cartoon with Galileo explaining to some priests the evidence that he found for the true movement of the planets and the Moon.
One priest did scream: “Fake News!!!”
With another one saying to Galileo: “You are Woke too!!”

All human institutions advance social agendas. The question is just which ones. A library that deliberately attempts to avoid all social agendas is embracing a particularly dangerous social agenda.
Agreed. Putting up a Pride Week poster is a social agenda. And not putting up a Pride Week poster is also a social agenda. When people claim they don’t want any social agendas, they mean they only want their own social agenda.

Every time you are thinking about the idea that government should put its fingers on the scales to advance social causes, you should ask yourself if ypu would be okay with that if Donald Trump or some other hated figure gains power and decides to use government functions to move HIS agenda.
No, I’m not okay with Donald Trump and his followers moving their agenda. My agenda is that everyone should have equal rights, regardless of their race or gender or religion or ethnicity. Their agenda is that straight white men should be superior to everyone else. Their agenda is wrong.
They will anyway, no matter what people on the other side do. They only stop dominating, exploiting and abusing people when actively stopped from doing so, not because their prospective victims hamstring themselves.
At any rate, the simple existence of a library is “advancing a social agenda”; specifically, the access of written works to the masses free of charge. That’s literally the point. It’s not possible for them to not advance a social agenda, they can only choose which ones.

So, if a library is in a very wealthy, conservative, white community, it ought to actively promote - say DEI or poverty issues?
Having a display on a bookshelf about DEI or “poverty issues” is NOT “promoting” them. No one is being forced to read a particular book. My God, what sort of snowflake feels oppressed by the mere mention of something outside their experience?
“very wealthy, conservative, white” people need to get the hell over themselves. The world is comprised of more than just them.
I think that advancing and promoting the idea that all men are created equal should be a core mission of the US government. It’s in their founding documents.