I doubt the modern divorce rate can even begin to approach the rate of change wrought by just the maternal death rate alone.
Looks like you exaggerate a little. I think a half dozen wives would be unusual.
George Washington had only one wife, though no children. Martha had 4 children by her first husband. She outlived both her husbands. Thomas Jefferson only had one wife, though he may have had other relationships. John and Abigail Adams had 6 born children (a seventh was stillborn). John didn’t remarry, though Abigail died first; looks like he was about 53 when she died.
The Lincolns had four children. Ulysses S. Grant had four children. His wife outlived him. When Andrew Jackson’s wife died, he did not remarry. They had no natural children.
But. the issue is not how many spouses someone has, but the tendency to dump a spouse and find a new one through boredom, or another reason besides death.
If someone assaults his/her spouse, or is unfaithful, that should be grounds for divorce. But now we have “no fault divorce” and “irreconciable differences.”
If Republicans want to restore morality, there should be less divorce among their members and no adultery or homosexual acts.