We have one report, by Ken Rosenthal. As Austinfan noted, it's entirely possible that Klentak and Kapler concluded that Young's contributions as assistant pitching coach were more valuable than Kranitz's contributions. There's no way in the world that a fan could make that determination, one way or the other, because fans aren't privy to what's actually said and done in the cages, in the locker room, in the bullpen, etc.
I can well believe that the Phillies made the move because they didn't want to lose Young (as Rosenthal reported). But I have to think that implies that they value Young's contributions more than Kranitz's - not because they wanted to "keep Young happy," but because they concluded that he's more valuable than Kranitz. The people actually in the trenches - the pitchers, the manager, the GM - are the only people in a position to make that evaluation. By the way, "keeping Young happy" was EDmuch's characterization; Rosenthal didn't say that. His tweet:
So, unless we get pitchers coming out and saying that Kranitz got shafted, that they'd rather pitch for him than for Young...then I don't think we can conclude that Klentak made a poor decision here.