Generally Disappointed in "The Lies That Bind"

I finished reading Kwame Anthony Appiah's The Lies That Bind and was totally underwhelmed; the book feels like a missed opportunity. He spends 6 chapters demonstrating, quiet eloquently in places, that Sturgeon was right, only to finish up with the world's most milquetoast coda.

If it turns out, as Appiah has so ably demonstrated, that our conceptions of religion ("creed") or race ("color") are badly mistaken, then surely that has some implications for current discourse? I mean, he writes "The modes of identity we'e considered can all become for of confinement, conceptual mistakes underwriting moral ones." (p. 218), which would be a great segue to the second half of the book where he talks about common moral mistakes in the present. And yet the book ends at p. 219 with a bland call for us to recognize our shared humanity.

What gives? I mean, its a glaring and obvious omission which cries out for explanation. As far as I can tell Appiah has a lot of credibility with the public at large, which puts him in a good position to say something that people will actually listen to. His decision not to venture into an explication of moral mistakes stems from what?

I can't really even hazard a guess... maybe he just didn't want to? In any case, The Lies That Bind ends up feeling like a joke without a punchline.