Proven, IMHO, by the ease with which many atheists have fallen into alternative faith-based belief systems. 21st century America is increasingly atheist, but no less religious.
Side note, but horoscopes aren't fully to be thrown away[0]. IIRC the main idea was that the month of birth is/was related to seasonal human activities, or illnesses seasonality, which would have a tendency to affect newborns/newborns-to-be strongly.
I'm not so sure. The common person definitely cannot give scientific explanations for most things, but between modern medicine, computers and all else, society is drowning in very hard proof that science is an effective and worthwhile endeavour, in a way that i don't think most religion is. Though admittedly that does not seem to completely stop people form breaking away from science the same way as they break away from religion (see flat earthers).
For example in Buddhism there's the notion of karma: if you do something bad/good, you'll meet bad/good things in return. Now, there's the "fantasist" interpretation, with reincarnation & cie, but there's also a pragmatic approach: if you keep doing bad things, people will want to get back at you, you'll get a bad reputation, and others won't want to deal with you anymore.
Or, frowning upon sodomy, considering that feces are a transmission route[0] for many common infections. Same thing with advanced promiscuity and STDs. Or the importance of sturdy couples (marriages, Confucianism) for kids's well-being (see e.g.[1]).
What I mean to say is that, we may have a very hard proof that religions were effective to help societies, at least to persist.
[0]: https://en.wikipedia.org/wiki/Fecal%E2%80%93oral_route
[1]: https://ifstudies.org/blog/children-first-why-family-structu...
But all these things can be explained and understood rationally without the need for a divine book forbidding things for frivolous reasons (or at best, without any stated reason).
Basically, people don't really need a bible to know that poop is dirty (a parent or a doctor can explain it just fine) but when the bible explains that one shouldn't put one's penis in another's anus (does it actually say it, or does it just vaguely talk about an ill-defined action called "sodomy"?) it doesn't give valid reasons.
So in the end, while religions do have a positive role on some aspects, they also encourage thoughtless actions or even actively discourage rational thought because of gaps that shouldn't be questioned, or outright inconsistencies.
Perhaps for a lot of those people "if you do bad thing big man in sky punish you" is the most convincing argument.
A Chinese friend once told me about the evolution of Confucius's interpretations: in the early days, a woman married to a poor excuse for a husband could be expected to leave him, for example so as to avoid her kids to imitate their father. Centuries later, breakups were strictly "haram".
The Muslims aversion for pork is another example.
The precise knowledge we have about poop's dirtiness is recent (e.g. first bacteria observed in 1676[1]; first virus in 1892[2]). Strictly speaking, we don't need divine books, but at some point, it probably was the only widespread, battle-tested option. Remember also that it was at a time with no Internet, and low literacy levels; people were different.
(I'm not intimate with the Bible's relationship with sodomy).
There's also the fact that the vast majority of people aren't receptive to rational arguments. Well-known, ubiquitous example: advertisement.
The fact that the Bible and others don't (always) give a why, do you think it's really a bad thing? There are valuable side-effects (let me leave this as an exercice).
[0]: https://intersol.ca/news/organizational-culture-and-the-5-mo...
[1]: https://en.wikipedia.org/wiki/Bacteria#History_of_bacteriolo...
I'm not sure this is a good argument. Science "works" in the same way religion "works" for many people.
“Atheist religion” is more like NPL, scientology, UFO cults, The Singularity, simulation universe etc.
And the false believes have far reaching impact, like polarization in society and deaths. Just today I read that Dutch vaccination rates are lower than ever [1]. Diseases like polio are no longer a 3rd world problem, but could revive in Europe as well.
[1] https://nos-nl.translate.goog/artikel/2512681-vaccinatiegraa...