[SunkenCiv]

It should come in handy (as the article states) to figure out provenance for the much more numerous clay items like pots and jars. So much of the clay shards winds up in the rubbish tips because there’s no identifying features on it — now there may be. This will work out as a proxy to determine, for example, the departure point of ancient shipwrecks, and the origin of the rarities such as the clay tablets found in the archive at Hattusas, the Phaistos Disk on Crete (interesting because the characters on it were made with dies, rather than hand cut, implying that it was manufactured; at least one modern scholar thinks the PD is a fake), and the 26,000 year old ceramics of Dolni Vestonice.

[JimSEA]

So much of the media for writing can not survive time. Only in the desert would papyrus survive. Luckily the Chinese left cast bronze and turtle shells with records of their written language. How many civilizations wrote on wooden slats or banana leaves or some such in a humid climate? It would explain the "sudden" appearance of writing in many locales.