RFK was a primary nominee along with other Democrats that wanted to challenge Biden for the spot.

it is insane you have to even write this but here we are... :)

Though not unprecedented in US history, its a huge problem in my book.

huge problem but more of a problem on a democratic party side. while trump did not want to participate in the debates, he won the primary by getting enough votes to become a republican presidential nominee. not a soul voted for kamala to be democratic presidential nominee... while many different "excuses" were made why her campaign failed this by itself was an issue that was not discussed enough. in my small personal circle 2 people specifically said they voted for trump in large part because of this