IMO this kind of thing goes back to perceived effort by the coaches and probably small things they teach in practice and how the players execute them on the ice. One thing I like about Vesey is that he can be quite good at anticipating passing lanes and jumping in to steal a puck, he can forecheck pretty well, he hustles around the ice looking to make things happen, and coaches eat that **** up. They love it. And it's not a bad thing, but it starts to become missing the forest for all the trees. Coaches see these smaller things and they love it, they see a guy executing some things that they're trying to hammer home, they think "this guy gets it" so they gloss over the fact that player might not actually be productive at all, or for all their hustle, not that good defensively.
They see another guy like Buchnevich who maybe doesn't forecheck as well, isn't flying all around the ice all the time, maybe isn't hitting all the little marks that the coaches want him to do, but who actually produces. But he's still marked as "learning and figuring it out" because he's not yet doing those things the other player is.
In a perfect world, a player does all the little things the coaches want as well as produces offensively, but like I said I think coaches sometimes miss the bigger picture when focusing on the small ****. Sometimes it's not a *bad* thing to be all hard on a player to tighten up their game and pay attention to the details, but you also can't really ignore production just because maybe a guy isn't playing the details perfect.
All that said, I think Buch will get a bigger role next year and is still a big part of the Rangers plans. For all the complaints about AV and young players, he's done a good job with the young guys the Rangers have brought in, at least in terms of giving them bigger roles and building them into the team. People bring up his tenure in Vancouver as how he's so terrible at developing young players (most of which weren't that good to begin with) but he's been fine with it in NY.