I hate Bowman as much as the next guy, but this trade is fine. We already have a plethora of prospect depth at D (which we still have as the deal involves another D prospect coming back), Carlsson's stock was dropping, you bolster your center prospect depth with Borgstrom. Wallstrom sucked here and he wasn't going to be re-signed anyway, so at least Stan got something for him.
You never know how truly good a trade will be until the players pan out or not, but in the present, it isn't a horrible move for a rebuilding team. This move is actually encouraging in my view because it shows that Bowman gets that he should be rebuilding and stockpiling picks/prospects. The Hawks got the best piece of the trade with Borgstrom, who is a former first round pick.