This is a great post. However, according to your graph, first tool use occurred 3.3 million years ago. A quick google suggest Homo Sapiens have been around for approximately 300,000 years. So apply Fermi's paradox to a smaller scope - ask why we only see civilization within the narrow window of the last 10,000 years out of 300,000 years despite Homo Sapiens being in their current modern form for so long?
Here's a graph to help visualize the last 50,000 years https://www.dandebat.dk/images/1579p.jpg
Hopefully it's obvious that something changed coincidental t... (read more)