I don't think anyone thinks Biden did well. Its that Trump looked like an asshole. I don't see how its any different than himself every other day, but I guess a lot of people saw a new side to him and didn't like it.

"Stand by" to white supremacists. Being proud of his actions on covid. Making fun of biden for wearing his mask too much. People think it was a shit show. And generally speaking, incumbents lose during shit shows.