Don't know where you're getting your information from, even before we get to your wild, unevidenced speculation.
More complete writing systems were preceded by proto-writing. Early examples are the Jiahu symbols (c. 6600 BCE), Vinča signs (c. 5300 BCE), early Indus script (c. 3500 BCE) and Nsibidi script (c. before 500 CE). There is disagreement concerning exactly when prehistory becomes history, and when proto-writing became "true writing".[2] However, invention of the first writing systems is roughly contemporary with the beginning of the Bronze Age in the late Neolithic of the late 4th millennium BCE. The Sumerian archaic cuneiform script and the Egyptian hieroglyphs are generally considered the earliest writing systems, both emerging out of their ancestral proto-literate symbol systems from 3400 to 3200 BCE with earliest coherent texts from about 2600 BCE.
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The earliest chronologies date back to the earliest civilizations of Early Dynastic Period of Egypt, Mesopotamia and the Sumerians,[3] which emerged independently of each other from roughly 3500 BCE.