Your first quote leaves off the important bit: against the headwinds of Google culture. I agree, the first half of the sentence is a common scenario among CEOs, it's the 2nd bit that makes it especially challenging.

I disagree that it was "fine" because the people who were respected and held up as prime examples of Googlers – for decades – almost always had nothing to do with the ads business. This sends a signal to the rest that the ads business doesn't really matter, it's not the important work, it's akin to the janitorial work that has to happen so the rest of us can work here. If you do that long enough you end up with people optimizing towards things that aren't aligned with the needs of the business. It was on autopilot, relatively, compared to other areas.