Stephenson’s editor didn’t. The result is the worst book with Stephenson’s name on it.
The first 2/3 of this weighty tome (I assume – mine came encoded as a very large number) is a series of technical infodumps on space technology of the early to mid 21st century, with a framing plot that destroys the Earth and more than 99.9999% of all living things in the Solar System over the course of three years. There are a couple of characters in there who recur often enough to keep their names straight. Most characters die or disappear quickly enough that job titles would do just as well. I didn’t find any of the characters particularly sympathetic. Perhaps you have seen a slushpile book in which a first-time author has worked out the entire history of their fictional universe, and tries to tell that to you with the names of fifty legendary characters that you should definitely remember? This is like that. If the parts of Anathem and Dune that you really enjoyed were the glossaries and appendices, you might get more out of the first section than I did.
Then Stephenson skips 5000 years. The “Seven Eves” of the title are the seven surviving fertile human females at the end of part 1; their descendants, about 3 billion strong, are the subject of the second and far more interesting part of the book. It’s still not great: it is mostly a semi-utopian travelogue novel, where a viewpoint character visits many named places on the map and talks to people who come from the other named places. (Yes, there’s a map with named places on it.)
Had I been the editor, and strong enough to say no to a heavyweight best-seller, I would have cut the entire first section and started off with the second section. SF readers are used to picking up clues about a fictional world, and doing so is actually fun for most people. This… not so much.