“Were the decisions that followed Henry VIII’s divorce totally unnecessary?”
Those decisions made by him in his Church of England? He was a heretic at that point.
Furthermore, it is said of Henry VIII that in his heart he always was and remained a Catholic. He just wanted things his own way.
So his teachings bent the rules to do it.
Well, maybe...
But once he broke from the Church, he ran riot over all the Church holdings in England. He not only confiscated Church goods but proceeded to destroy and raze Church buildings, abbeys and monasteries...
You can still see many of the remaining ruins...true devastation.