the core was drafted by Tallon - Tallon deserves and always has a **** load of credit...I don't think anyone is/has ever not said that.
but the main difference is Tallon got to draft when this team was ****, his picks were top 10 picks for a number of years. I still give him credit for making the right calls with Toews and Kane and Seabs...but where Tallon really impressed (him and his scouting team including Bowman) is the drafting of Hammer, Buff, and Brouwer...the rounds they drafted those guys still to this day impresses the hell out of me. And Keith in the 2nd round, was magic!!
Bowman has had some amazing picks as well - Shaw, DeBrincat, Saad, Sikura, etc...but look at average draft position between the 2 GM's, one had the chance to build this thing, the other could only try to replace players here and there constantly picking 25th and later - need to keep that in consideration as well.
I loved Tallon, I will always defend a lot of what he did, but Bowman has done a lot as well, so much retooling here, and him bringing in Panarin alone puts him well on par with Tallon and those picks.