Weird, why didn’t Whitmer, klobuchar, newsom, warnock, pritzker or hell buttigieg work their names on to the ballot? Why didn’t any of them qualify for the debates instead of Biden?
The answer to those questions is the answer to why we have Biden instead of whoever you like better. And it’s also why they couldn’t win against Trump at this time. Literally none of the people you listed have the widespread support that is needed to satisfy the gape of the fence-sitters like Biden does. It’s unfortunate but true.