For my part, I’ve worked with people who sincerely claim to have never had a good manager like the one you describe, informing their opinion that management borders on expensive futility.

I think both experiences are valid. I think good managers are in as short supply as good engineers are, and good people generally. Both hiring markets tend to be markets for lemons. Hyper growth startups that need to fill headcount can’t afford to be choosy, and within companies like this the Pareto principle applies. Unfortunately many people have decades+ of experience with the 80% and have never witnessed the 20%.