100%. If you sell off too many veteran leaders who hate losing it can lead the culture and attitude astray, and if goes on for too long the players can become desensitized to losing.
Lamoriello did well in assessing his greatest needs as number 1 centre and number 1 goalie. Blueline needed work but it was fair to project Rielly as a middle of the road 1. Bozak and Kadri were nice, but you'd love them a lot more as your 2-3 if you can add a two-way franchise centre at the top and knock them down a rung. Veteran wings in JVR and Komorov on the roster + Marner and Nylander who project as top line talent on top of Hyman, Brown, Kapanen etc
With all this in place he found a way to compete every night but lose enough games to bottom out and give himself the best odds to draft that franchise altering centreman then trade for a legitimate number 1 goalie without giving up anything he needed to keep.
Buffalo is a perfect example of how it can go wrong. I don't even know the problem, but I suspect its poor leadership and an entitled star. O'Reilly seemed to allude to that on his way out, but much of that is open for interpretation.
I'm not entirely sure how much credit to give Lamoriello for Matthews, but I do know I could make a case that Matthews and Anderson were arguably their MVP's over the next 3 years and the greatest driving force in their turnaround so it seems pretty disingenuous to give zero credit to the guy driving the bus who picked both up in the span of a few days.