Well, actually, we do. But the changes are exclusively internal. They are predicated on what happened in GFII, principally his murder of his brother. The weight of that enormous moral faux-pas must have been crushing as he aged. As he said, he killed his mother's son, his father's son. He not only took Fredo's life away from him, he also took it away from his mother and father. Taking Mary and Tony away from their mother also had its moral consequences. GFI & II were very event oriented; GFIII was not. But that was one of the points of III: the decisions we make dictate the life we lead.

"Generosity. That was my first mistake."
"Experience must be our only guide; reason may mislead us."
"Instagram is Twitter for people who can't read."