Operation Hit Cap Floor

Lol you wish siegs is untradeable

Virtually all of those teams you mentioned aren't going to be over the cap, so they don't have to trade players and add sweeteners.
Now the Leafs might be one team that trade Mrzarek with a sweetener.

For Chicago that may be true, reversing that wouldn't effect much either. For Edmonton, though, they could make a big splash with the money freed up from Kassian. For Murray and Johansen, those deals have several years left for both of them so, especially for Ottawa, it's not just about this year but about two years from now

I get that Johansen is slightly overpaid, but NSH isn’t giving up a first to move a guy with 54 points in 66 games.

Nashville is a playoff team this year and has $26 million in cap space next season for 7 roster slots, with Forsberg the only player of consequence to re-sign. They can afford to pay him $10 million (which they won't) and still have $16 million to fill the 5 remaining places, and, as @josi4norris so accurately points out, Johansen isn't exactly a useless mouth. In short, there's no reason for the Predators to have to move him at all, let alone pay to do so, let alone give up a first-round draft pick to get rid of him.