Inherent in the text of technical books that reveal what people did is an attempt to persuade the reader why they should do it, too. In some ways this reveals the central, myopic conceit at the heart of Google: if you don't have Google's problems, you should. And I'm not sure why anyone who isn't Google should just accept this premise.
That's not to say that the premise is unacceptable. I'm sure that there are people who want to participate in a thing that looks like Google, except that they'd rather start it from scratch than join the one that already exists. Perhaps those people want to have Google's problems.
Now we have a piece, expanded from a talk, by one of the editors of the books that persuaded organizations that, if only they would squint their eyes a bit and turn their head, they could make the problems of their organization orders of magnitude smaller by so many metrics look like the problems of Google. And now, perhaps, Google's answer to Google's problem wasn't quite right, because it didn't involve...something? It could be philosophy or human-centered design, and I wouldn't be surprised to find Google bereft of either, but it certainly isn't going to be found in a paper by Google (ostensibly, a Google answer to a Google question) that predates the first book by nearly a decade. It isn't going to be found in people for whom these things are afterthoughts rather than guiding principles. Instead, shouldn't we be asking whether we let SRE as a Google answer to a Google problem be a solution outside of Google in the first place?