Good insight Eric. The questions you raise are as important as those you answer.

The problem with Biden is that he is a "non-candidate". He is not going to WIN the Presidency but is a body waiting to catch the position by default. That is a position inherently full of anxiety and uncertainty not just for winning but what comes after.

Interesting that Trump too has fallen, in some ways, to a default position with the "hidden" voter you decribe.