Well, at the dawn of human civilization our finest tools were hewn rock. Now we have computers and have stood on the moon.

It took a long time because we started with nothing. Absolutely nothing.

I like the article but I think it's missing the forest for the trees. The reason why things took so long relative to current rates of progress is just because knowledge compounds upon itself.

Early on in a system defined by compound growth you will have slow growth. Then eventually exponential growth. This is what we've experienced.