I understand his decision. His kids are small and need him at home. Also his wife did get sick and already almost left before. He have a title in the pocket. What he possibly could achieve more if his seasons don't go to the plan? Maybe he will go same route as Ogier and will be back, but only part time, so he will be more with family.
That situation is just saying that this format of events is too tight for everyone. Kalle, Lappi, Ogier, Tanak all saying the same thing. You don't have much time for your own. And FIA want to increase number of events... For who? Eventually everyone will start doing half seasons if this thing will not change.
I mean what could be done? Maybe decrease number of stages, days, kilometres? I thnk that marathon era is long gone. Also if the route would be somehow smaller I think there would be more tight battles also, as everyone would be more focused...