Nobody wants a weakling for President. If Biden can't take that, how the Hell would anyone expect him to stand up to Xi or Putin?
None of the following possibilities would be surprising:
* Biden withdraws prior to the debate, claiming he has flu-like symptoms, possibly covid.
* Biden gives debate closing remarks, saying Trump’s debate performance tonight should “radicalize” all Democrats who must vote like “our lives depend on it, because they do.”
* Debate begins. Trump makes a statement. Biden responds that Trump has destroyed the economy, trashed the Constitution, will take away Americans’ healthcare, encourages violence, refuses to leave office peacefully, puts lives at risk, and calls Trump a fascist. Biden says he thus “refuses to further engage” with Trump, and Biden angrily walks off the stage.
Or some such nonsense.