My take on this is that it could be degrees. TL4 may have more people at broken level of literacy and innumeracy, improving up until we hit modern and mature public education at TL6.
What has this got to do with Gaming?
Is a person here more developed than Alexander the Great?
My answer is: Yes. Many people receive education and opportunities Alexander the Great, Julius Ceasar, and all the great people of history would envy. Every War College in the modern world pulls out people who would out manuver and out think Alexander, Ceasar, Scipio etc.. because they have the knowledge of everyone who had before them, and the science to be able to reduce risk and uncertainty, and the ability to know how to decide because of cognition sciences. Everyone now has in them, more points spent, than anyone else in the past of equivalent social standing or of similar majority.
Technology is also seen in the way we discern from facts from errors and bad data. We right now have technology that allow us to cut through Illusions/Deceptions and Ambiguity. We have science; unfortunately Information and Processes are huge chunks of data that can only be put through a very small hole of the human mind. It takes Data Size over Data Acquisition Rate = Time to absorb information and be able to verify it. We are much in the dark because as a bunch of Humans, there are enough of us who have to much at stake to let Information reach the Equilibrium of Objectivity.
Low tech is better?
One thing that I am hyper aware of is that old nagging about old ways are better. If we go back to the oldest days people are subsitance living, that means NO other free time. That means less free to save up for the future, and a whole world with people who only live by the huge cost of getting anything done. When looking at the future and the past, we may be self reliant in the past BUT we don't have the freedom to do what we want (especially when we consider realistically how much time anything takes in Low Tech).