I dunno, these debates scare me. Harris/Walz is surging right now, and Trump/Vance is tanking: this gives Trump/Vance a chance to inject their brand of FUD by throwing shit against the wall and seeing if anything sticks.
For example, I suspect Vance is going to try and nail Walz with Walz's 1995 DUI. That'll be a hard one for him to talk his way out of, it's ugly and then later his campaign lied about it.
Could also be that she's looking for a chance to say "I'm speaking" again.