[Albion Wilde]

Disagree. In spite of its flaws, it finished the story of a man’s utter failure and search for redemption.

[Dr. Sivana]

it finished the story of a man’s utter failure and search for redemption.

Not just Michael, but Vito, too. Vito started this whole thing because he was made unable to provide well for his family. In searching for control, he had to control his children, and unintentionally put Michael in a position where he HAD to take over. Vito's oath on his grandchildren, even if Michael was the one who executed the plan that broke the peace, set in motion the chain of events that led to Mary's death, and also the unnamed Corleone son #2. Vito died before it all played out, but wherever he wound up, perhaps he saw the consequences of wanting to be the puppetmaster.