As a former Trump-hater, he knows the other side's arguments and can dispel them with cool and aplomb.
There are crazy Biden shills in the media who think Harris will easily win the VP debate, but I’m like, they keep waiting and hoping for the big ‘moment’ where things change for Biden’s campaign and I can’t think of any time in history when a VP debate of all things altered things for the campaign behind. Also, Vance will win the debate, like come on.