I don't think it's wrong to criticize, Bill. But you also have to take into account the equipment and the technique Henri was using for some of those shots. Leica rangefinders, even now, take a second to focus. If you want the kind of portrait Henri was after, by the time you lift the camera and focus, what you were after has disappeared. So he did what I do on the street with my E-P1, he pre-focused. Considering the speed of the film he was using in the early days, f/3.5 (wide open on early, collapsible, Leica rangefinder lenses) was essential for most of his portraits, so he didn't have much depth of field to save him.
Finally, a whole lot of those shots were sudden decisions. His picture of the Curies is a classic example. He came through the door, lifted the camera, and made the shot, before they'd even been introduced. As a result, he got something unique. His portrait of Ezra Pound is better as far as focus is concerned, but if you can believe what Henri wrote about it, he sat in front of Ezra for twenty minutes and neither of them said a word to each other.
In the end, a lot of his portraits are technically faulty, but in most cases he captured something about his subjects that a formal portraitist like Yosuf Karsh would have missed.