I have a new GE fridge, and the freezer gets above 32 during defrost mode. The repair man says that's normal?

I have a new GE GTH18DCRVLBB, and I noticed that the ice freezes together every few days, not to mention frozen pops would be mushy and ruined.. I put a wireless thermometer in the freezer and found that, while the temp was usually around 0-5, it went over 32 degrees everyday or so--sometimes all the way up to 40. The repair man who came replaced the new thermometer, but told us due to new energy star standards, that freezers now go through rapid defrost, where they can easily reach these temperature, and there was nothing we could do about it. He recommended putting bottles of water against the back wall to defend the rest of the freezer during daily defrost cycles. It sounded to me a lot like he was full of it(a freezer should keep things frozen), but I was wondering if anyone else could give me an educated opinion.