I've just picked these quotes up as they stand out for me...
"What does your son think it needs to happen here to move forward?
For some people, ignoring the past does not work"
"Apart from an apology, what exactly is the son expecting?
"Ask him what he wants"
FWIW, I doubt he exactly knows. I do agree however that his wife, who suffered quite a bit, may have altered his thinking. it would be strange if she hadn't, but it accounts for it coming up now not when he was in his 20's.
a problem to me is that its not unusual in our culture nowadays to rush to Blame instead of understanding and accepting.
Of course where there is clear and strong abuse then blame is appropriate
...but not the fact that most of us carry hurts from less than perfect parenting inevitably, but it was good enough parenting.