Kaliyev is a poor skater, so maybe I am contradicting myself a bit. Although there is a big difference between both the draft capital used on him and the style of play. But I will bring up the essay The Hedgehog and the Fox to describe how I view Kaliyev. If you are unfamiliar with the essay, it basically says there are two types of people, Hedgehogs who do or focus on one thing really well and Foxes who are more well rounded/ focus on multiple thingsl. Kaliyev is an ultimate NHL hedgehog, he is an NHL player because he shoots the puck at a level that not many in the league can. He really doesn't have any other skills that are really NHL caliber. His entire success as an NHL player will be judged by how many goals he scores a year, that is it, that is how you evaluate him. And I think that playing the style he plays as a catch and shoot player that will do a lot of damage on the PP that skating can be more easily overcome. For a center you take #11 in a draft, that is going to be required to have the puck on his stick a lot and making plays, it's just harder to overcome the poor skating.
Again maybe this is a contradiction, but to me that is why I think AK can overcome the poor skating better than Gabe might be able to.