Some major mistakes made by Biden in the debate:

He made immigration an issue with amnesty
He made fossil fuels an issue with ending oil industry
He laughed at cheap gasoline
He linked himself with Obamacare/Bidencare
He pushed the green new deal
He pushed $15/min wage

Dark winter
Endless Shutdowns
Placed economic success below every other issue
Opened himself to cages
He promised Mask mandate(very small issue outside of blue areas, but very emotional one)
He opened himself up to his racist past.
He had no defense for corruption charges.

He had no hope to go with the change.
He failed to make the debate about Trump
He didn't take enough medication
He played not to lose and did not play to win.
He played to his base allowing Trump to play to the moderates
Conclusion EPIC FAILURE...EPIC