He can have whatever opinion he wants to as far as I am concerned. But to go to this ceremony, one handled by a prestigious and giving institution, where media was present, and say this? He has got be a huge jerk (mind you, that is not the first word that came to mind).
Well, I told you my feeling that it is the duty of a guest to be polite to the host.
I think he broke that duty, but my opinion is that he believes he has a duty to remind all Europeans how badly they have treated jews. He may be a person who doesn't think as much about building friendship as he does about retribution.