Well, not really.
He praised his wife for putting out a generic Instagram message, "I support my Jewish friends and the Jewish people," adding to the graphic, "If you don't know what to say, just say this in your feed."
Seinfeld is not a confrontational comedian, and his comments were that his wife found a non-aggressive way to say what needs to be said. OK.
But then Seinfeld said that most of those types of statements "is going to trigger someone, is going to inflame - we are so quick to inflame, right? Both sides of any debate - women, gender, everything - this is the culture we live in: Flashpaper. Instant, violent, verbiage."
Not to nitpick here, but is being against Jew-hatred a matter of "debate"?
Yes, people will instantly jump on you if they believe that your opinions on abortion or Trump or pronouns are wrong, but most things have reasonable people on both sides disagreeing. To throw being against antisemitism in the same bucket as those issues is saying that supporting Jews as having equal, human rights is controversial. And when one crafts a message of support for Jews it must be done in such a way as to not upset the antisemites.
I'm certain he didn't think this through, but the idea that support for Jews is something that needs to be wordsmithed, to be carefully thought out before saying it publicly, is a tacit admission that the Jew-haters have a valid point, too, and we must not offend them.
We wouldn't say that we must not offend racists or misogynists. Why, with Jews, is there a subtext that support must be nuanced to avoid backlash?
