I’m afraid Biden made that comment in the spirit of the worst kind of dog whistling. He’s sending a signal, even if he’d never actually accept a Republican as running mate.
He’s telling voters they can feel safe electing him, that he’ll maintain America’s elitist, racist, exclusionary, white-nationalist status quo. A vote for Joe is a vote to keep things how they are, just without the insane instability of Trump in the White House.
No thanks, Joe. I never really considered voting for you, anyway, but you’ve killed any chance you might ever have had with me.