It's fascinating that over 400 indigenous tribes lived north of the NA desert border between US/Mexico and there is zero evidence a single one had a written language, while the Maya and Aztecs on the other side of the deserts were writing for centuries.
Elamite, Sumerian, Akkadian and other languages of that region were written on clay... which lends very well to mass production and extremely well to preservation. They also had large populations and urban centres.
These are all very big multipliers of evidencence. A clay tablet has >1000X more survivability than papyrus, velum or even painted pottery.
Meanwhile... there isn't much writing in central and south America either... even when/where population density and urbanism is high.
Khipu, knitted strings, are the most common known writing system. There's evidence for the existence of other writing systems... but not much of it. Hence, undeciphered one-offs.
You also need to consider that writing has different uses. Most development of literacy examples start with some pretty limited use cases.
Writing isn't like fire, instantly useful to everyone everywhere.
Depending on what you consider South America, and it is a Chilean territory, Easter Island has a mysterious script which seems to have caused endless arguments. The Easter Island system certainly looks like a script, but where it comes from and whether it was invented there is another question. Easter Island isn't near anywhere.
There's a 1991 film (and earlier novel) called Black Robe that fictionalizes what it might've been like when the first Jesuit missionaries introduced this powerful black magic to the natives in the 17th century.[0]
More conventional forms also, to some degrees and in some times and places.
Many of the ancient people's of Mesopotamia leave little or no trace of their languages. Hebrew, an iron age language, leaves only scraps dating to the iron age. One of 2-3 complete sentences from the whole kingdom of Judah is an inscription commemorating the completion of a waterworks project for Jerusalem. They wrote it on papyrus and it does not survive.
Neighboring iron age cultures are known from single artefacts.
The Easter Island script was seemingly written on banana leaf.
There is no deep archeological record of knotted strings.
Speculation from a sense of evidence is trick. Personally, I think writing and proto writing existed and was invented and lost many, many times. Thousands maybe.
Also, while impressive... A scaled up in advanced literary culture is not necessarily necessary, or even useful.
Egypt for example, are those Monumental temples and pyramids, mortuary hieroglyphs and what not necessary? Useful?
It's hard to distinguish between the outputs of the civilization, and its objective needs. There may have been many ways of doing complex, large, dense civilization.
