The democrat party have no bench. That is why they cheat and try to jail their opponents.
Your point is correct....there is marginally a ‘bench’ for the D-Party to pick up candidates from.
If you review state governors...most have crappy results to brag about. This guy from Kentucky (Beshear) is about the only one that seems capable of bragging-rights.
In the case of Newsom....the counter-campaign against him can be hundreds of videos of failure around the state of California.
Even if you were to review Senator options...Fetterman is the only one that might get people marginally hyped up.
So you are left with AOC?