Here's the best copium I've got that isn't just "it'll be fine": they didn't dip into the league-best (by the reckoning of many) prospect pool at all to make the trade, and #4 would have been used on a D who would be a few years away from being an impact player. So you're trading #45 and Crevier to forgo the development timeline and remove a certain level of uncertainty on the pick. Fair enough
The flipside is that Byram hasn't shown he's the guy they need him to be for this trade to pay off, so you're still hoping for a certain level of improvement that is far from certain to happen, he has a worrisome concussion history, and he needs to be paid and suddenly has a ton of leverage to demand a crazy contract. And value-wise it feels like the Blackhawks paid the cost you'd expect for a guy without those question marks
It just feels like a bad gamble, not a move to put a team over the top but to claw back some respectability. I don't think it cripples the rebuild or dooms the future of the team, pending whatever extension he gets, but I don't think it's a good trade as we stand now. Would love to be wrong