Joe was considered to be and still is a bottom of the barrel candidate in the primary.
Then it was clearly demonstrated that the other thirty- including Kamala Harris- would be even worse than Joe in the eyes of dem voters.
I guess this is what sends a tingle up your leg.
You can shuffle the deck anyway you want but the dem voters were not excited about any candidate for more than a couple months in the primary. So if you point out that they eventually had to pick people that were clearly losers that is mathematical given, after the door closed and they stopped adding candidates.
Winning the Dem Party Special Olympics got you a disabled candidate confined to his home.