Yes, I have been soundly corrected in several posts.
It is easy to get them all mixed up...three John S. McCains!
He was also in extremely poor physical shape by the end of the war, had dropped to below 100 lbs. One of the things they found out early in the war was that there were too many senior officers (O5 and up) who were not up to the rigors in a war environment. There was a concerted effort to get them out of positions of leadership and promote younger and fresher men into those roles.
But men like Nimitz, Halsey, McCain, Mischner...they were in for the long haul, because they knew what they were doing.