We lost 3 homegrown Rangers in the offseason, one of whom was the face of the franchise and de facto leader of the team, in Lundqvist, Staal, and Fast. Replacing them with Jack Johnson is not going to offset the void that those veterans filled.
I think the front office did a piss-poor job of identifying leaders/veterans that can set a good example for a very young team. Even post-2005 lockout when the team started integrating younger, homegrown players into the lineup, we had a solid group of vets such as Shanahan, Straka, Drury, etc., that the players could look to on the ice and in the locker room for leadership. Zibanejad, Kreider, and Trouba ain't it.