Imagine if Biden played this like his opponent and just started firing off tweets accusing Trump of ordering Bill Barr to kill Jeffrey Epstein. The press would have a stroke.
Even if Biden played it coyly and said, "There's a lot of unanswered questions there and I'd imagine a new Attorney General would be interested in taking a closer look," there'd still be a fainting couch shortage.
I'm not saying Biden should go out of his way to make it an issue necessarily, but boy would it be nice if a reporter asked him about it and he was ready.