I think there is some truth to the idea that social media is making people dumber. What this article is calling “tribal allegiance” is essentially the same as what I have been calling “team sport.” For most people, social media is an approval-seeking system. The main attraction is the “Likes.” As such, it tends to draw people who crave confirmation/approval. Many people pride themselves on how fast they can get likes (particularly on Instagram), and they come to rely on their own tribes to “Like” their posts regardless of whether they actually like them or not. It’s a team-building ritual. It’s very much like two people saying to each other: “You look great!” “You look great too!” The point isn’t to objectively evaluate each other’s looks. They are just scratching each other’s backs. It has nothing to do with the merit/substance of the content.
The lack of a dislike button also encourages the use of these platforms as an emotional support system. Anyone who expresses disagreements is seen as undermining the cohesion of the team/tribe, the support system. Such a person is a threat to that system.
It’s fine to use social media to scratch each other’s backs if the contents are, say, photos of a birthday party, wedding, food, or pet. But even for more serious matters like politics, back-scratching still remains to be the motivation for many. This discourages independent/critical thinking. When someone posts a political article, we are supposed to show our agreement or approval. The correct answer/response is always implied in the post. If we deviate from that expectation, we are deemed clueless.
Given how influential social media was in the last election, the lack of independent thinking, we could say, did make our politics dumber. It’s not exactly the fault of social media; like MSG, they amplify whatever social proclivities we have.