Jim Clyburn made Biden's nomination happen and Joe knows it.
After that, it was given that a black woman would be selected for VP. Clyburn and Camp Obama and Biden wanted Susan Rice but Biden was also having problems with satisfying the progressives so Rice would not work along with some other reasons. But Amy was never going to happen as VP with Joe being so beholden to Clyburn and the black vote he controlled.
In 2020, a lot of pundits kept up the drumbeat about "wait until South Carolina, wait until South Carolina, and the black vote kicks in" in regard to primary races. All valid, but it is going to be very dicey in 2024 if the dems show up in those southern states and Joe is not running but the first black vp is not in the lead position or has already been ousted before Iowa as happened last time (and her approval has only gone down). No sir. I do not see it generating many black votes if the black woman has been set aside and -for example- a white male, hair-gelled metrosexual governor of California is in the lead- for example. And you cannot pretty that up by putting a black woman in the vp slot again. It begins to reek of "the women and the blacks can only be number two but we are supposed to be the more progressive party."
Be careful dems. That same Jim Clyburn, Southern black voter primary scenario that worked last time could be a land mine waiting for you this time if it looks like Kamala was unceremoniously set aside. I don't exactly know how you navigate that but we shall see. Most likely Kamala's rating will be so low that she will not run and save you from some problems. But you still have to show up in South Carolina and similar states with someone who works for the black vote. Hillary suddenly adopted a fake southern accent as needed. Hopefully we will not see Gavin Newsome or BootyBoy do that.