I do believe, however, that he could still resign before the end of the year (October surprise?) If Kamala starts sinking in the polls, they could decide that Biden has to step down due to a health crisis to be named later. They can then market her as the incumbent to try to save her candidacy - "She stepped up and took control, guiding the nation with a firm hand in a time of crisis."
Becoming Prez would be contrary to her current hide the ball strategy, pretending that she has nothing to do with the current admin...
Hmm...consider the media jubilation and fawning they’d have over “President Harris”, it’ll be “oh the energy this just injected into the race - she’s the FIRST BLACK WOMAN POTUS!!!!!!!!!!!!!!!!”.
It would not surprise me at all. She’s tanking...propped up by the media and fake polls. They need something else.