Samuel O'Brien, the most obvious reason for not having Biden run again is his age. He will be 86 years old, should he serve a whole second term. And Biden, even if we like him, is no Henry Kissinger.
Democrats would be wise to believe whoever is running on the Republican side is young and formidable.
Buttigieg is an excellent choice. He is clever and sees the big picture. Also LIKABLE and an extraordinarily skillful campaigner.
Biden taking his time to decide serves no one well. Although Buttigieg could swiftly put plans together, other newer talents need time to surface.
I invite you to read "Please, Joe, Not Another Term."
Many thanks.