I told you, they could have run a collie dog. Nobody voted for Biden, you just had a record turnout of people who thought they were stopping Hitler. Trump's behavior after the election did nothing to dispel that impression.
The big thing we learned both in 2016 with Hillary and 2020 with Trump is that voting against someone is now more appealing than voting for someone, and drives bigger turnouts. In political-speak, the negatives are more important than the positives. That's the only reason Trump won in the first place. And Trump's negatives are through the roof.