Yes? Chiarot has historically had success in that kind of usage, specifically with Florida while playing with Weegar or Montour at the end of the 2022 season.
Pettersson is good and I like him a lot, but he's a solid middle pair DFD. It's not the end of the world to include him in a deal to add Erik Karlsson.
Chiarot has good size, not that he'd be allowed to really use it to full effect with the Mike Sullivan Pens (Petry has good size too) and I wouldn't necessarily hate him as a 3rd pairing guy but then we'd have no #2 LD at all though Smith would be interesting to try there.
As everyone knows, Karlsson channeled the spirit of Bobby Orr last year and put up 101 points. With the Pens I'd be willing to wager some HFBoards cash that he gets way closer to 50-60 points than 101 next season.
But Dubas wants to make a splash, and a succession of Ellers, Acciaris and Nietos isn't splashy at all even though Mike Sullivan has to be delighted. Also, EK on the team would stimulate fan interest at least for a little while and maybe get the team back to selling out without having to fake it with "student rush" giveaways and crap like that.
Bottom line is that from the perspective of making the Pens a true contender to go deep in the playoffs, I don't see the NEED for Karlsson, especially if it's going to cost someone like Petts -- who I agree is hardly one of the core players, but he might be ready to quietly move into a Dumoulin-type role here (Dumoulin from when he was good, I mean) and that's got some solid value.