I have often thought the same thing. And I also wonder why we wouldn’t be much more technologically advanced than we are at this point. If you look at technology in the past 100 years, shouldn’t we be much more advanced at 6 million years?
Six million years? IIRC australopithicis was around three million years ago. The Homo genus is only two million years old, and humans 100,000. Rapid technological progress also requires language and writing.