He may have inherited the rights to the core, but it was Kyle and only Kyle who gave them all super player-friendly deals and paid them all as if they were proven winners before they'd won a damn thing.
They had the two richest extensions in Matthews and Marner in league history, outside of McDavid, coming out of their rookie deals. In fact, Marner got the richest extension of any RW in league history coming out of his ELC, and Edmonton got McDavid for 8 seasons rather than Kyle walking Matthews to free agency over 5 years only 1M$ cheaper. He basically cost a season of Nylander by waiting to the 11th hour before caving and giving him everything he wanted - which he could have done 6 months earlier and had him in training camp.
Say what you want, but Lou Lamoriello would have never, ever, EVER handed out those contracts. EVER.
When push comes to shove, Dubas has squandered every possible asset available to him. He gave away cap space to kids who hadn't accomplished anything yet and made them very, very rich. He traded draft picks for guys who did nothing to help the team. He made some decent trades, but also some terrible ones and let the acquired assets walk so he could focus on his vision of a team, and undeserved loyalty to guys who didn't deserve it (how do you not get rid of Holl and give Lyubushkin the same dollar amount given he was a VAST improvement over what we had?)
I really think Kyle will be a very successful GM one day, but not here, and not until he gets a lot more experience under his belt. He's not eaten his piece of humble pie yet, and hasn't shown an ounce of humility that maybe, just maybe, his vision for how to build a team is flawed. Up this point, though, he's considered himself the smartest kid in the room and the walls are about to come crashing down hard.