Assyriologist Irving Finkel believes Gobekli Tepeh is or is evidence of writing or proto-writing. That's 12,000 bp. There are ice age artefacts that may represent writing-like symbolism.

The super-old artefacts themselves are only a hint... but I think more recent artefacts demonstrate that invention of a writing system is relatively common. We tend to think of invention of core concepts as the magical event, with expansion and proliferation as derivative or even inevitable. But... I think this may be backwards.

In general... I think purely intellectual feats that can be completed by one person happen over and over. Otoh, we intuitively underestimate the role of context. Availability of trade goods like paper and ink. The application of writing to uses like tax collection, trade contracts, religion, scholarship or whatnot. Those all require many people. Whole societies, economic and political structures.

IMO, this is the uniqueness of the early bronze age... for writing and other things.

A lot of the writing dirth of the european dark age relates to the scarcity of papyrus. Writing medium seems like a trivial issue. You can write on skins, or bark or shingles. But... that doesn't scale and doesn't lend to the development of writing as a big deal. The invention of cheap paper-making was as important as moveable type for the "Gutenberg Revolution" to take place.

Rongorongo is an undeciphered script from Easter Island. From the handful of surviving examples, this is clearly a highly developed script... developed independently on a small island. https://en.wikipedia.org/wiki/Rongorongo#Corpus

The Cherokee Syllabary is a fascinating example. It was invented by Sequoyah. One guy. He had access to paper, ink and examples of english writing. He (seemingly) didn't have any information on how english writing worked. He borrowed letters from english... but he used them to represent syllables with no relation to latin. EG: the letter "D" represents the sound "A."

The ingredients for the invention of a full, advanced, newspaper-ready language were (1) one motivated genius (2) paper and ink (3) an example of how far the idea of writing could take you.

There was no proto-writing stage. It wasn't limited to personal seals, charms, prayers, accounting or short documents. I think the key here is example, a demonstration of potential. Sequoyah had seen books, letters and longform text. So, he went straight to newspapers, constitutional documents and suchlike. He taught his young daughter to read and the timeline from initial conception to widespread, advanced literacy was just 20 years. https://en.wikipedia.org/wiki/Cherokee_syllabary

Writing and proto-writing may have been invented tens of thousands of times. Neanderthal proto-writing would be a paradigm-shifting find... but it wouldn't shock me that much.

The breakthrough inventions that tend to unlock a flood and punctuate our understanding of history... I think these are often more trivial than we expect. What matters is the ethereal and hard to describe "context." The addition of one or more trivial ingredients like a writing medium. Abstract "meta" like "writing should be used to write whole books." The sociability of the inventor.

The growing appreciation of Elamite sophistication adds to the shockingly large corpus of large, advanced civilizations that have existed in history. There are so many of them... and we don't even know what most were called.