Carolina is gaining assets that they can use as currency or just develop for themselves. They could flip, the Toronto 1st, Bokk, or Edmunson into other pieces down the line. Or by having those extra assets, maybe they are more comfortable in trading off another piece for something of need.
For example, the blues knew Shatty was not coming back in his final year, so they traded him for a first plus Sandford. The next year, they were on the bubble of a playoff spot but falling pretty hard and sold Stastny to the Jets for a first plus Foley. The following year they traded 2 firsts and dumped Lehtera, for 3 years of Schenn. The next year, they traded picks, plus Tage Thompson (a first round pick) for ROR. If they hadn't had those extra picks from earlier trades, they may not have been comfortable with paying the price on either of those players.
We don't know what Carolina is going to do with these new pieces yet. Maybe they just make the pick and let Bokk develop for themselves, and use Edmundson just this one year. But maybe if a Brayden Schenn type forward, or whatever Carolina's big need is, becomes available, they could have the expendable assets available to close the deal while other teams may not have enough in the cupboard to make the trade. They knew Faulk was not in their long term plans so they didn't just let him walk as a UFA.