Wow. I'm old I guess. Science moves so fast, and those of us who are not in the field are hopelessly behind on current theories.
I was blown away by the documentary because it was very different from what I was taught. I had always been presented with the theory of microbial life becoming increasingly complex, with, perhaps, an occasional setback here and there. The idea that the first known life thrived in an environment that would be toxic to life as we understand it, and the idea that this first life exhaled oxygen, which was a toxin to those little swimmers, and ultimately killed them off, and that a few mutated survivors that thrived on oxygen became the sources of all life on earth, is completely new to me!