Maybe ten+ years ago there were so many awful GMs that having a good one was a major competitive advantage but now I'm not sure there's even a single bad GM. I hear the names that thrown around now as terrible GMs: Dubas, Dorion, Ron Francis, Holland, etc and I don't really see it to be honest. A few bad decisions but sensible ones, you don't get GMs like Dale Tallon anymore doing completely awful mistakes, no one is trying to build through unrestricted free agency anymore, everyone is basically trying to build through the draft and create cup windows from a pool of young talent which is the only way you can.
Which means Yzerman, who imo is an above average GM, can't do magic. He can produce this team and prospect pool after 4 years, which looks pretty middle of the road and not destined for great things, the way say Buffalo is after stockpiling picks and young talent for years. Tampa was built by Stamkos/Hedman and jackpot draft picks like Kucherov/Point which are mostly dumb luck imo. The cherry on top was the Drouin / Sergachev swap which Yzerman deserves full credit for though.