Agreed on your neuro take. It would seem that the rigidness is somewhat reinforced by the pervasive mechanism of digital feedback. As we now can see clips of stupid behavior being propagated online as easily as opening our eyes and tap a screen, the rigid behavior of an overt narcissist is now on display as a model for lesser equipped minds to absorb. The narcissist acquires a visually recognizable position of power through their actions, and this makes them highly desirable by those lacking control in their own life. The audience is global... And where the terrain is fertile.. the said audience also votes for their model.
Social media is a toxic stew of identity based narrative reinforcement. Custom tailored to your specific, and I mean really specific, narratives. Does your identity revolve around religion A, hobby B and C, political views D? The algorithm will feed you exact pro-narrative pro-identity content. Did you react to the rage bait style things that we tried out on you? Awesome, now you are getting even more toxic nonsense streamed to your brain. It is genuinely scary. It just creates and strongly reinforces it. It is like we created a way to chunk memetic hazard into a series of small unidentifiable pieces. The net result? No one would be like "If you open this door you become an extremist and will have really rigid identity beliefs" who would open that. But clicking thumbs up or like on a "funny" political meme? Sure why not.
so .. i guess.. if technology is meant to trigger our impulses then the world is slowly going towards the direction dictated by the impulses that form the largest cluster, pulling the whole environment in their direction. Just like a carriage with many horses that cannot be controlled if a group of horses decide to pull right and go into the ditch. So we will have to endure the fall of everything just for the impulsive unevolved people to learn their lesson. Kind of a grim view... but seems like it right now.
I don't think it is generally hopeless like that. I think some people will funnel in that direction. We are humans. Our consciousness is the original hacker. It took over the hippocampus and used a mostly spatial 3D storage system for our RAM, which is kind of funny when you think about it. We haven't evolved nearly as fast as this technology and many people will point to that and say we have bypassed evolution in the sense that our brains are not equipped to defend against something like social media. And it is true, the layer of indirection is not something our consciousness works well with. But I think it cuts both ways. Deep down, the human mind is still a machine primed to keep you alive from getting eaten by a tiger. It loves not having to spend energy and there is very good evidence of how all that works (Friston's free energy principle, our memory as bayesian priors, our consciousness as a machine using those priors to run something like thousands of monte carlo simulations to figure out what priors match the simulation the best). But it is a messy machine. It is often wrong and will choose higher energy paths. And, I think... something in most of us is just hard wired for certain kinds of "authentic" experiences. I don't know, I have a little window of optimism about where this all ends and that although we are weak to social media, social media is weak to some fundamental aspects of our machinery that map towards authenticity (this is a very vague argument, but I could point to a lot of evidence around this and how we react to nature and other things that can't exist in social media that do exist in the physical world). For example, why do small children often love rocks? No real reason. They are just interesting particularly because of their non-utility in industrialized society. They are novel. The brain has no real category or survival use for it. But there is a kid with a pocket full of rocks after a day at the park.