This is simply false. Reproduction of papers is an academic issue but your claim is at the very least hyperbolic. The scientific method has proven to be by far the most successful method of investigating the world around us.
A lot of science (both back then, but especially now) is less hard and is more optimized towards being accepted. Psychology, Anthropology, Geology, Paleontology, many fields of Biology, and many others are all about social proof, since really what else can you use? There are too many lines of judgement that have to be drawn for any of it to make sense in a hard ‘verifiable’ way.
And hard science still requires reproducibility, but a lot of that is getting more niche and harder to verify, rather than more directly verifiable, so it is also falling prey to ‘acceptability’ vs ‘verifiable correctness’.
Going back even further Historically, it was very hard to afford verifiable correctness, so very few people could actually do it. Pretty much either very rich people, or people with rich rich sponsors - which also often required or provided social proof/acceptance.
Religion helps wrap the whole thing up in a way that is marketable, and secrecy protects the ‘trade secrets’ so any sort of professionalism can be supported for further work or development. And because people need to eat.
Which are closely related to secret societies like the Freemasons [https://en.m.wikipedia.org/wiki/Freemasonry], and the common pattern of secrecy among Alchemists [https://www.tandfonline.com/doi/pdf/10.1179/amb.1992.39.2.63].
I’m not clear about what you mean with ‘tiered system of information based on achievements’ separate from ‘secrecy’. That pattern was, and still is very common in religious and military institutions that I think anyone would call high on ‘secrecy’.
In broad strokes, how is that different from modern day security classification systems, and/or things like information access based on rank?
One very obvious difference between now and then, IMO, is the massive difference in wealth and population between now and then. That allows specialization and optimization to much greater degrees than possible before.
I think the English language is great but complicated cultures are ill served by translation.
Biblical Hebrew commonly has 3 verbs in a sentence to semantically express a thought. The cultural ideas and concepts are hard to express in English.
Any translator needs to understand that aspect. Without that understanding important subtleties could be lost.
All of that is to say the word secret in English has connotations that may not exist in the original idea.
I’m not saying there weren’t societies that held information closely, I’m saying the motivations and details are likely lost.
What % of population today can actually understand let alone reproduce the papers being published today. And this is not just about practicality of it. Is there a motivation to even reproduce it ?
I am not saying "science is bad". I am saying science has the same fate as religion.
It is not obvious to me.
You have some other ideal I assume.
I see you as unwilling to defend your ideas.