He just did. He announced he has covid and is heading to Delaware to isolate.
And apparently Schumer told him to step down "For the good of America."

Honestly, if Trump wins, I wouldn't be surprised if someone tries to take him out. They'll stop at nothing to get rid of him. I know, I know. Tin foil hat theories. But I can't imagine they let him win. So they'll try a last minute switcheroo on Biden, and they'll try for push the mail in votes, etc. This is just my opinion.
That snake story is a remarkable and isolated instance of Trump's self-awareness.