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.