The earliest written history and myth, produced by the Sumerians circa 27 BCE, describe very long periods of human habitation and urban civilization prior to the beginning of history. The earliest known war memorial, the Stele of Vultures, predates historical writing by at least a few centuries (crude writing, reminiscent of a shopping list, is older); evidence of war dates back to around 12,000 BCE with standing armies dating to perhaps 5,000 BCE. Uruk, Lagash, Eridu and others were large, thriving cities long before there was written language; conservatively, over 5,000 BCE. Given the many changes in the channel of the Euphrates river, there is no reason to think we've found the first layer of the first city ever founded, nor is there any reason that Sumeria must have been the location of the very earliest human city. Various sites in the Levant show continuous human settlement, if not actual urban development, going all the way back to the end of the last glaciation. Villages, if not actual cities, date back at least 20,000 years and there is no reason to think we've actually discovered the oldest village ever settled by human kind; a city is just a scaled-up village surrounding public structures. The earliest pottery dates back 18,000 years; the earliest known beadwork dates to circa 80,000 BCE. Stone tools date back to around 2.6 million years ago, far older than Homo sapiens has existed as a species. And advanced stone tools have existed for nearly as long as Homo sapiens, about 200,000 years.
The Gulf of Khambhat discovery, though impressive, has not yet had a definitive date established, owning in-part to the commonality of ancient wood on the seafloor of an area that was once heavily forested prior to the current sea-level rise. Gobekli Tepe has had a definitive date established, circa 10,000 BCE, but to there is no evidence of year-round habitation or domestic agriculture. These are very remarkable discoveries, but had Earth actually been visited by benevolent space aliens with advanced technology, posing as now-long forgotten gods, I’d expect something more technologically impressive than the knapped stone tools, stone bas-relief, pottery sherds, beadwork and mudbricks that human kind already had developed on our own.