Can you expand on the other things that the article says? I don't see many new angles, all I see is reformulations of the exact same premise. Claims of strength vs weakness are directly analogous to professing in-group allegiance. Replacing tribalism with symbolism doesn't change the underlying mechanism, especially when a few paragraphs later they directly link symbolic thinking with "authoritarian attitudes", completing the circle back to tribalism.
> Claims of strength vs weakness are directly analogous to professing in-group allegiance.
They are mostly orthogonal imho. I can be strong without being in-group, and vice versa. In a group whose ideology is worship of power, then I can see a relationship but they aren't at all the same. For example, there are those who take the role of the weak who are worshipping power (and sometimes wanting it) and a defined power structure, like people who identify with being 'betas' and incels.
That's only a small part of what the article says.