Interesting but I don't think this is true. IMO Debrincat was brought in to begin instilling a winning culture. PD knew that the competitive window wasn't yet open but it was time to inject a new attitude, one that would pay dividends after this year and even next, with or without Debrincat, and eventually propel the team through the playoffs.
This team should be better than it is. Entering the season we had one hole (RD) but bad coaching is holding us back and the Zub injury exposed how thin we are on D, which yeah, should have been obvious.
The Duchene trade was much more of a last ditch attempt kind of trade. We didn't have near the same depth as we do now but it was done out of desperation to remain competitive while we had EK and Stone and make a pitch to get both to resign. Miscalculated but also magnified by Karlsson beginning his regression that year and the absolute clusterhump that that SENS team turned into with a terrible start, injuries, Hoffman drama, etc...
So one trade was done as we were walking out the door (Duchene), the other while we are about to walk in it (Debrincat), imo. At least this one can still easily be salvaged.