What I thought I heard him saying in that speech was that Trump was wrong to think it was possible for him to overturn Biden's win, which isn't quite the same thing as saying Trump was wrong to seek it. Not so damning about Trump: making a mistake isn't as bad as wishing to commit treason, and as I heard it the implication was that he was incorrect rather than wicked. "Wrong" can mean either, so it was a clever word to use.