You can't sell papers or get page clicks by continuing to write positive stories after the tour has ended.
So while, during the tour, you can talk about how open and willing to pose they were, that has to turn into being excessively stage managed.
During the tour, you can talk about how Kate lit up while feeding the baby rhino. After the tour, that has to turn into criticism that she wasn't feeding sick people in Calcutta.
During the tour, you can publish pictures and talk about how loving the two seemed on the safari (during which they had a jeep full of photographers ahead of them for all those photos, so I've no idea how it was "private"). After the tour, you can't sell that anymore, so it turns into "lightweight vacation".
At the end of the day, the press cannot continually sell the same story. They have to, and do, spin the narrative so that it's new and fresh. The difference between the royals and the press is that the royals are honest about the fact that they have press officers and a head spin doctor. The press pretends to be neutral while spinning like crazy in the service of economics; I find them painfully disingenuous.