We didn't really get a chance at one at the draft , I prefer Slaf over Cooley so you can't blame them for that one , not sure why the fanbase thought 3 top picks was enough , teams usually need more than that at least a few top 10s sprinkled in there
While I may agree that we could use more top-end prospects, I'm not sure there are many examples of what you are describing. How many Stanley Cup winners in the last few decades had more than 3 top-5 picks?
Off the top of my head :
Pens : 87, 71, 29, 58, and Staal + Kessel at different times.
Colorado : Erik Johnson, Landeskog, MacKinnon, Makar. Rantanen top 10.
Florida : Ekblad, Barkov, Bennett, Reinhart, Tkachuk.
The Leafs have four, but they won f*** all. Tavares, Marner, Matthews, Rielly. Nylander top 10.
So among champions : not the Caps, not the Bruins, not the Blues, not the Knights, not the Hawks, not Tampa (Stammer and Hedman, that's it I believe, with Sergachev top 10). Not the Kings. And among finalists, you can add Sharks, Flyers, Rangers, and many others.
The Habs could ice 5 next year : Demidov, Reinbacher, Dach, Laine, Slafkovsky. It's good, but it's not insane either. Goes to show it's as important to find gems later in the draft + having luck with the draft classes when you pick high. Getting a Reinbacher is not the same as getting a Pettersson even if it's the exact same rank.
But you have to also develop them in a winning culture. You dont want to be Buffalo.