Semantics
PUBLIC ENEMY #1
Larkin is more NHL ready player than Nylander, he plays that excellent 200 foot game while Nylander still needs some work in that department, especially if he's gonna play for Babcock. I also think the state of the Leafs factors in, they probably don't want Nylander to be around for what looks like will be a tough season in TO. No reason to risk hurting his confidence and stalling his development. He's better off spending another year with Marlies, keeping his confidence sky high, creating chemistry with his future teammates.
Doesn't change the fact that Larkin would be in the minors for a couple of years. Babcock demands that his players be over ready, which is impossible in Larkin's case because he's only played five professional games.