This is exactly why his campaign is functionally as dead as Biden's brain, at this point. Whether his campaign staff realizes it or not--Because Biden isn't making his own decisions-- they're stuck in a death spiral. All of the policies and points that he made earlier in his campaign aren't just being walked back, they're being outright reversed because this is no longer a "sprint to the middle" that you usually see in traditional politics, nevermind the fact that said 'sprint' generally doesn't occur with 60 days left until an election. All of the policies that he was hammering onto the podium were forced to be as far-Left as he could reasonably make them, because he was trying to be the most-Progressive candidate on the stage, as that was the only way the DNC could think to counteract Donald Trump.
They threw all of their chips into the Progressive stack, mistakenly assuming that was their biggest voting bloc, not realizing that Bernie's radical wing of the DNC is actually fairly small and pursuing what that group wants is done to the detriment of all other groups. These policies were all so extreme to the Left side of the field (Free healthcare for illegals, no borders, universal healthcare, green new deal, etc) that even just inching them back isn't enough to bring you in line with the moderates, you need to dump them outright if you want a snowball's chance in Hell of appealing to your sane voters.
But even if you push all of that off to the wayside, his campaign is falling for a completely fatal trap, and I don't know if they even see it: They do whatever Trump tells them to do. Joe Biden says he won't go to Kenosha, so Trump goes to Kenosha, and this forces Joe Biden to go to Kenosha. Donald Trump starts hammering on "Joe Hiden", and his campaign starts pushing him out onto the stage to prove that they're totally not hiding Joe, forgetting that the reason they were hiding him in the first place is that every time that Joe makes an appearance, he rams his foot down his own throat.
If Joe Biden's campaign won't agree to the debates, Trump will just start flapping his arms and making chicken noises, and ten minutes later Joe will get shoved out of his napping chair and onto the debate stage so fast that he won't have time to put his teeth in. Trump says Joe Biden can't jump, and Joe immediately jumps as high as he can to prove Trump's wrong. He has Biden's entire campaign wrapped around his finger and they're too short-sighted and angry to even see that it's happening.