I don't know of many pathologists who have willingly retired. Seems like most either die at the microscope or have an MI and are forced to quit. I know of one pathologist, not at my institution, who was in his late 60s and was asked to retire from an academic place, so he quit and got a private practice job.
There are also a lot of people who "retire" but keep consulting or teaching until they have the second foot halfway into the grave, or until their ability to speak disappears.
Personally, I don't get it. If I had enough money to retire comfortably, I would retire. But maybe when I reach 65 I will find that medicine still stimulates me a great deal and I can't quit. What it would hope is that it still stimulates me, but I also have better things to do with my time.
Of course, when I am 65 all doctors will be making near minimum wage working on an assembly line at "diagnoses 'r' us," existing merely to sign off on a diagnosis that a computer or series of computers makes. Why would we even exist at all, you might ask? Because malpractice lawyers will need someone to sue, and those diagnosis-making robots will just be too tough to depose on a witness stand. So the system will make it so that physicians make just enough money to have it be worthwhile to continue working instead of quitting and becoming a legal assistant.
You may ask, of course, why the legal assistant wouldn't be a robot too. That's a story for a different day.