>>the guy was there for 16 years, so it's probably just time for a change
This would make sense to me if the announcement included what he was doing next.
Often "retiring for personal reasons" is code for something they wouldn't want to put in a press release. Especially when the retiree is less than 50 years old.
It's possible. Not typical for the type of person that ascends to that level though. He and Matt were perhaps the two most well known names in that group to the outside public. Both with similar departures (or semi-departures).
The scuttlebutt I heard on him is that he opposed using machine learning and artificial intelligence techniques for search, specifically deep neural networks.
I can understand his opposition, Google search results have been monotonically declining in quality recently in my opinion.
I wouldn't be surprised if this is a polite way to sweep him out of the way. It's pretty much a golden parachute if so.
This is of course all speculation and hearsay based on what I heard about him a few months ago.
This would make sense to me if the announcement included what he was doing next.
Often "retiring for personal reasons" is code for something they wouldn't want to put in a press release. Especially when the retiree is less than 50 years old.