There’s a interview with Thomas Chatterton Williams in the New Yorker.
I think he makes his case much more thoughtfully than the actual open letter. Which may be the point-- perhaps Chomsky and some of the other signers will individually write something elaborating on the letter’s premise. He also says that the letter was a collaborative effort.
It doesn’t answer some important criticisms, though, and the Williams still claims that the canceled authors remain part of “polite society”-- that rings hollow. (I’m not familiar with Williams. Perhaps he’s said some horrible things. In which case, I apologize for my naïveté.)