I was thinking about this and how it is to be gracious when there's an award or competition on the line. Anyone can be gracious in victory. It's easy at that point to praise your competitors because you have the proof in prize. It's far harder to be gracious in defeat. Inarritu isn't especially gracious in either, but as this shows especially not in the latter.
I wonder if Inarritu realizes that his award was pretty much entirely contingent on having Di Caprio playing the part of Hugh Glass. If not for that, and the whole narrative about how Leo is due, he wouldn't have gotten the directing award. Lubezki might have gotten cinematography, but I'm not sure even about that. Without Leo, The Revenant wouldn't have had the wide swath of nominations.