How do you prevent post-tribalism from becoming yet another tribe?

That's the neat thing, you don't! The very idea of post-tribalism relies on a false narrative. There is an appeal to a mythical past when the Enlightenment was one wonderful big tent and everybody was pursuing the shared project of advancing the knowledge of the human race together. Then those mean and wily post-modernists came and upended the notion of truth. This is all blatantly false. Nobody has ever agreed on anything. As soon as you find a group of people who do agree with you, and there is another group of people who don't, then baby, you've got a tribalism going.

It's a rhetorical move to claim as your heritage some kind of truth that once went unchallenged and is now questioned by people with nefarious purposes. Nothing more.

Rhetorical moves are the primary vehicle of politics. You say something and people resonate with your message. You believe frivious "claims around heritage" are not deeply meaningful to people. Do you truly believe that should artificially overcome family ties, traditions, cultures, and, customs? (…Why would you even want to?)

Seems like it's all just a ploy for corporations trying to remake the world as suits them, helpful to have interchangable workers with no meaningful culture.

Fair point. But I guess my problem with the post-tribal narrative is that it feels especially hollow. It's not rooted either in some kind of particularist commitment to a religion or language nor some universal notion of human brotherhood or dialectical materialism. It's built on the myth of consensus. "We all used to agree about this! What happened?" That just feels like an insecure basis for an intellectual movement.

Do post-tribalists even make enough children for them to survive very long? I'm reminder of the Shakers, a religious group that rejected sexual relations between men and women and were famously celibate. They did adopt children at a rate far higher than non-Shakers, but when the supply of children to adopt dried up, their numbers plummeted. Today, there are only 4 or 5 of them left, and when they die, so too will their ideology/religion. Post-tribalism won't survive either, I think.

https://en.wikipedia.org/wiki/Shakers

That was my impression as well. As TFA says, "Hitchens took no issue with efforts to mobilize people around identity-based causes", which is what I understand "identity politics" to mean.

He seems to associate "identity politics" with bad arguments as applied to those causes. Which, sure, same. Bad arguments are bad, regardless of what they're applied to. There are an awful lot of bad arguers whose goals align with mine.

In that sense, "identity politics" sounds identical to "woke" or "politically correct" or any other right-wing buzzword used to dismiss a left-wing idea out of hand. To quote Hitchens, "as if those two words constitute an argument".