Jerry Seinfeld became a mic-cradling, cereal-eating, “did-you-ever-notice”-ing avatar of American Jewish life with a brazenly shrugging persona: a merry indifference to weighty material as a comedian and in his megahit TV show about nothing, as petty and apolitical as he seemed to be. Now — off-camera, at least — Seinfeld appears to have reached his post-nothing period. Since the attacks of Oct. 7 in Israel and through their bloody and volatile aftermath in the Gaza Strip, Seinfeld, 70, has emer