Apparently, Apple was wrong or partially correct depending upon how you view the data. One of Huawei's phones is thinner if you do not count the bulge at one end and another manufacturer nobody knows makes a thinner phone sans a bulge.
Apple should have left it at "the iPhone 5 is the thinnest phone we have ever made." (parahrase)
Seems to me if an Android maker said their phone was the thinnest in the world and a bulge at one end added three or for MM to the thickness, the Android side would ignore those iPhone users crying shenanigans and forget about the bulge because it does not count.
Mr. Cook either lied or he made an honest mistake. One is not the same as the other.
I do think Cook and others speaking for Apple should learn to check facts with greater care and if Cook has a problem, he should use an iPrompter. They/he should know by now that every word will be parsed and some of those writers hate Apple