I think the Bidens are actually trying to run out the clock on their Democrat critics, who were gaining significant momentum for replacing him on the ticket until the Trump assassination attempt took the focus off Biden. This Covid diagnosis is very convenient following his string of still quite feeble post-debate appearances. His recent grocery store photo-op was abysmal, for example. His inner circle is desperately trying to keep him out of the spotlight until he is officially nominated. There is still a lot of infighting in the Democratic party right now. Pelosi and other Dem leaders are trying to push Biden off the ticket, the official nomination of Biden as the Democrat nominee has been delayed, etc. We want Biden to remain on the ticket. His stubbornness and narcissism ensures a Trump landslide 😏