It would be nice to have a strong challenger
Under Biden, we've seen no meaningful action as the right to abortion was lost, housing scarcity has become a crisis for most Americans, another 100 billion unbudgeted was sent to another country's war, and there was zero meaningful progression on education, health care, militarizing police, or stopping the resurgence of fascism.
Voting for Biden is voting for team color and little else. The man is a shitty president more concerned with stringing together a coherent sentence and running cover for his son than doing anything for the people who got him elected. And the extent to which he is a shitty president is going to usher in an overt fascist when he tries to sell himself on his record in a year.