Mkhitaryan and Shaw's treatment shows the gulf in class of the management between Fergie and Mourinho. As Keane said Fergie knew what each player needed, and what they responded too. It's why he was harsher on the likes of Ferdinand and Keane. While at the same time he was a lot more mellowed towards a Ronaldo, who needed a different approach.
This is a different crop and generation now to his one at Chelsea and Inter. I'd say most of the current generation need the latter approach. It's why Ancelotti and even Zidane, have managed to get 2 CL titles out of that Madrid team. Seems like why Matic is now back to his league winning form, and Costa and Hazard are back to being stars.
From what I know about Shaw, hes from a fairly privileged background who's been a superstar since he was a kid at all levels. Mkhitaryan himself, has a previous history of suffering from low confidence. I don't know who in their right mind would reach the conclusion, that these are the type of players you publicly humiliate and breakdown to get a positive response from.