Completely academic exercise. The polls have barely budged, and Biden is the only man to have beaten Trump. Both men are known quantities, as are the respective party platforms. Just about every voter has a home team. You don’t abandon your home team because it got its clock cleaned - you double down. That’s why the polls have moved by a point or two. Voters are dug in.
Polling aside, due to election mechanics that prevent an intra-party insurrection, Harris won’t replace Biden, any more than anyone replaced Strom Thurmond or Ruth Bader Ginsburg. Dianne Feinstein was literally in a wheelchair before anyone was able to persuade her to leave. But it was voluntary - she had to agree. When they dig their heels in, as with Thurmond and Ginsburg, there’s not much anyone else can do.
Biden’s worked his whole life to get here. He’ll be damned if he lets anyone take it from him. Like every one of Trump’s opponents, he’s betting on Trump’s auto-destruct tendencies to give him a leg up. With four months to go, there’s still a lot of rope with which Trump can hang himself.
I don’t think Biden really cares if he is president. Jill on the other hand...
Dictator Brandon did not defeat President Trump. The election was stolen.