I'd agree with you that this would be bad for most companies I've worked at barring arguably one (Amazon, which is also gigantic) -- at any startup/medium sized

I'd agree with you that this would be bad for most companies I've worked at barring arguably one (Amazon, which is also gigantic) -- at any startup/medium sized company, these practices would not be right-sized to the work being done. Even during my tenure at AWS inside Amazon, I have difficulty believing this would be useful; for example, at AWS, we'd separate services by tiers based on how close to the center they were inside the internal service graph. Running EC2/S3 or another tier 1 service? Yes, you're probably going to index on moving a bit slower to reduce operational risk than not. Running a new AWS service that is more of a "leaf node" than a center node? You can go ahead and move fairly quickly so long as you're obeying AWS best practices, which while somewhat hefty by startup standards are quite relaxed by other corporate standards. What I wonder is whether this kind of heterogeneity would have been a better path for Google than what you describe. Or, is it the case that the sheer monolithic scale of search/ads at Google is such that it just wouldn't make sense, and that continuing to pile incremental resources into the monstrosity (and I mean this gently/positively) of search is what the company must do and so what the engineering culture must enable. But, as you might be alluding to, perhaps the current approach doesn't even suit the needs of the company and is purely bad even for Google's specific problems -- in that case, is it simply there due to cultural cruft/legacy? I haven't worked at Google before, so it's hard for me to say something based on my experience with it.