Loving the thread. Just a general comment on technology though: The tech tree of computer games is not an accurate depiction of how technology improves in human civilizations. Technology does not neatly "level up" to a certain state after the following prerequisites are met and by building the appropriate buildings and waiting a set amount of time.
According to wikipedia the stone age lasted about 3.4 million years. So a few million years of using literally stone age technology. So many thousand years of history is nothing in our history when it comes to technological advancements. We are currently living in a period of time where our technology level is improving at a literally unprecedented rate from what our ancestors would have experienced. Its not that there were no improvements in technology, but they were at a much slower pace. And technology and information was not shared as frequently as it is now.
And that does not take into account that technology levels can regress. The great pyramids of Giza were built ~2600BC. It would be thousands of years before buildings as tall would be constructed that tall in Europe. The method of making greek fire was lost. Presumably for forever. And even though they had a clear use for it, what with enemies all around. Some of whom eventually broke into their city, took it for their own and renamed it (and not before another group of enemies beat them to it first). Ancient mathematical proofs have been lost. Some probably for all time while others are being rediscovered. Some by mathematicians figuratively reinventing the wheel and some old documents are being recovered. The oldest are from thousands of years ago.
TL:DR version - Technology is a strange thing and does not progress at a set rate or even in a consistent direction. Our perspective on it is very skewed based on the period of time that we are living in.