Re: Amazon Tech level
There's also the isolation issue to consider. No contact with other cultures. Much of our technical developments over the centuries were results of one culture picking up something from another culture they contacted, and doing something different with it. It never really made sense that an isolated culture would not only have developed the airplane, but a faster and better one than than the various societies of the rest of the world had developed as the result of centuries of contact with one another. That's why cultures that had minimal or no contact with others were "primitive." It wasn't that they weren't as smart, naturally, as European, Arabic, and Asian cultures. They just didn't have the contact and opportunity to pick up things, and develop what they'd picked up for their own purposes.
Comparing where Japan was during their centuries of self imposed isolation, a feudal culture well behind their peers, to how they developed after they stopped being isolated, is another example. They learned, and adapted, and did it quickly, to the point where they lead in technology, now.