What are the implications of the similarities between the designs engraved on cylinder seals and proto-cuneiform for our understanding of the invention of writing?

Basically cylinder seals are a unique individualistic design to show ownership of trade goods. While writing served as an administrative, economic, trade-related and religion related symbological designs representing type, quantity for a trade transaction. the first set were simple symbological design stamps, others became cylindrical (round) where you could stamp and roll a very unique design as with all designs there is chance of your brand being mistaken for someone else's, so variety in design was essential.

This made Eanna, the central governing authority in Uruk a very important agency for ensure trade settlements, trade distribution and religious authority. It also served as a proto-bank once settlements were cleared.