My assumption on this site is that most people talk from the perspective of devs. So I assume your experience with Microsoft's documentation is also on the dev side of things. I can't speak to that, I'm a sys admin so I have a different experience. And my job has me approaching technology from the opposite end. From what I have seen, Microsoft's is generally pretty good. Not the best but definitely far from the worst.
I’m afraid not. Those docs would have been used by both sides, especially for non-prod environments but they were definitely operations oriented.
I would agree they’re usually good but when they were bad, they were real bad. And bad seemed to happen a lot more outside of the “big” internal fiefdoms at the time (Desktop, Server, AD, Exchange, etc.).
They did seem to hit a rough patch during the transition but the only thing I’ve seen is gaps here and there due to what I assume is incongruity between teams. Like tools being moved from an installer and therefore the installer docs but corresponding docs for how to get those tools not being created/updated elsewhere.