His hostility to the program as I understand it is that is CIRL doesn't much answer the question of how to specify specify a learning procedure that would go from an observations of a human being to a correct model of a human being's utility function. This is the hard part of the problem. This is why he says "specifying an update rule which converges to a desirable goal is just a reframing of the problem of specifying a desirable goal, with the "uncertainty" part a red herring".
One of the big things that CIRL was claimed to have going for it is that ...
If you had a defense of the idea, or a link to one I could read, I would be very interested to hear it. I wasn't trying to be dogmatically skeptical.