If you had a franchise center matrix and went through the various categories, Jack Eichel could conceivably come out much lower than you'd first expect.
In terms of individual peak numbers, a career high of 36 goals and 82 points and a 0.95 PPG average is not particularly impressive even if you factor in a Buffalo Sabres coefficient, whatever it would be. Puts you in a Mark Scheifele territory.
In terms of being a big game player, he's never really been in a position to have to deliver in a big moment, so he's untested in that category.
In terms of the "intangibles" category where you might compare him to older franchise centers who have more evolved defensive details, emergent leadership qualities etc, he's never even taken the Sabres to a middle of the pack level with his scoring, so we've never seen him have to demonstrate the other stuff to gain an edge.
In terms of elevating teammates, which could be an "intangible" quality, not a lot of guys have thrived playing with Eichel. Maybe Jeff Skinner when he had his one 40 goal year in Buffalo, but you can look at a number of high picks and a handful of bigger ticket acquisitions and it's not that good.