Well, for one, you land a McKenna and you potentially get 20 years of a franchise pillar to build around. Not really comparable imo. Dude's putting up insane numbers in Junior that we haven't seen, legitimately, since Sid 20 years ago. Could be a Kucherov in that he's a guy you make your franchise cornerstone, capable of carrying a team through the season/playoffs even though he's a winger as opposed to a center or blueliner. Sure, he could bust, but we'll see. That's the risk you gotta take in order to end up with a franchise icon for decades. You don't pass on a shot at landing MacKinnon because you have the opportunity to sign Kovalchuk or whatever.
Marner, you're getting the tail end of his prime years at 28, and it's with a team that's going nowhere--with or without Marner. How is this a comparable, even? The goal is to build back up through the draft. Not to emulate the Rangers, who for all of their regular season success the past few years, have f*** all to show for it and may be on the verge of crashing out anyway after their like 4 years of relevance this past decade. If you land a McKenna, you've got a prized centerpiece to build around for maybe decades. With Marner, you're just locking into more of this same barely in, barely out WC bullshit that's just gonna end in unavoidable bottom feeder stuff when Sid retires anyway. Which, I guess if you give a shit about a "thanks for showing up, enjoy golfing in a week" playoff appearances, means something. I couldn't give a shit about being a barely there team, hovering around the fringes with no promise of long term competitiveness or anyway. The goal should be to get back to being Cup caliber, even if it means some genuinely lean years as this team navigates the end of Sid's career and the post-Sid turning of the page. This team's already been losing for years, it's time to get building blocks for losing.
I dunno man, shit's f***in' dumb. It's a sad, desperate clawing attempt to remain even an afterthought in the grand conversation, and stave off the tough but required rebuilding years that will be happening whether you, I, FSG, Dubas, or Sid wants 'em to.