Did you read the analysis? I mean, the length of his critique should already tip you off, since Unz's article takes at least 2-3 hours to read. Gelman only criticizes Unz's assertion that Jews are overrepresented.
Gelman says in that critique that he agrees there is an underrepresentation of Asians.
That's not actually Gelman's analysis. He's just relaying some criticisms that were sent to him by Janet Mertz. Ron Unz responds to this, corrects some of his own errors, and shows his claims still hold. Then Gelman (proxying for Mertz) and Unz go back and forth way too many times, using way too many words and almost no data.