Trump knows where he is, who he's talking to, and what position he's running for, at all times. You also have a pretty solid idea of what his policies are. Progressives thought they had an in with Biden, but it was announced today that Sanders and Warren are to be frozen out of his administration.

Trump is a much bigger personality than Pence. Biden is an empty old husk. It is much more plausible that he would be controlled than Trump.