Didn't say he wasn't a top center, but he's not Crosby, MacDavid, MacKinnon or Bergeron or even Couts.
Couts has scored at a similar or higher level, but is also a perennial Selke finalist. We just don't appreciate what we have, "grass is greener syndrome."
In a vacuum, he'd be a great addition, but we're not getting him for free, he'll cost assets and a lot of cap room.
So unless you can work a deal like TK and Ghost (taking $10M off the books) and say #13, you could end up worse off.
And that's before you take the neck into consideration, Eichel wants an experimental procedure that still unproven.
You need at least 10-11 good players to compete at the top, two top lines (one top 10-15, the second 30-45), 3-4 20+ minute quality defensemen, a top ten goalie. So a marginal improvement at one spot can't come at the expense of other key positions.