I've found that something rarely considered is that even people who are less informed and less introspective have put /some/ thought into constructing their world view. Politics is usually a component of this, and at some level, at it's very basic, is built on top of the moral philosophy you hold as part of your world view. It's something so deeply personal, that it innately becomes a component of your everyday character. While it is true that a lot of people behave in tribalistic political manners, without "walking the walk" every day (Leftists call it "performance", Right-Wingers call it "virtual signalling"), on average if someone holds a political viewpoint about an issue and behaves in response to certain political news, it's a reflection of their fundamental worldviews.

It's not just a failure of people to logically consider arguments, it's an unwillingness to completely deconstruct and rebuild one's own worldview. When I press highly intelligent friends about this in discussions, what I'm often told is that discussing politics is exhausting for them, and that having arguments about is something they "lack the spoons" for. This is with people who are highly informed, intelligent, and typically enjoy argumentation and discussion based in facts and logic. Politics is different and special, because to change your mind you have to be willing to deconstruct your world view and everything that goes into it.

Of all the people I've had very deep political conversations with in my life, the one commonality was that they had all somehow achieved a level of introspection which allowed them to understand /why/ they have certain viewpoints. I'm not sure if their understanding is correct, because often it's tied to some prior personal private experience, but at least they could make a feasibly valid claim to understanding. I'm in an interesting position in my own world view, which has lead me to conversations which made it obvious to me that many folks who are on the Left that feel most viscerally about modern political issues do so because of a reaction to some specific personal trauma. Trauma that they may not yet have resolved, and that may impact their lives daily in many ways. Often those people are aware of their trauma, but they haven't yet been able to get through facing it and deconstructing it because it's emotionally painful, and any argument about related political issues which reminds them of this trauma elicits a visceral emotional reaction. This is in some sense is really what people mean when they discuss being "triggered", but even those people who won't discuss it experience this.

It's VERY VERY difficult for people to be brutally honest with themselves. At a certain point you can no longer lie to yourself, and you know all of what is in your head, where others can only guess. It's much easier to obscure the truth from other people, going through life structuring a world view that protects your emotional wellbeing based on a facade or partial truth. When you are deeply introspective, all of this is stripped away. Most of the people I've discussed this with have admitted that they have skeletons they don't want to face. I think to a large degree, this is just part of the human condition. All these aforementioned folks who seem to have gotten past this either had previously gone through many many years of therapy, which helped them emotionally mature, or they have some sort of empathy disorder which allows them to lack even empathy towards themselves and approach things from a less emotional perspective. Neither are common things in the general population, and thus we have people with visceral emotional reactions to nearly every bit of political news without really even understanding why they have their reactions. News organizations from a revenue perspective are incentivized to encourage and build upon these visceral emotional reactions as well, which just exacerbates the issue.

At the end of the day, the reality is that the vast majority of people integrate their politics into their worldview, but have never deconstructed it into first principles, and maybe wouldn't even know where to begin doing so. Trying to change their mind is like the emotional equivalent of physically assaulting them. You're forcing them to face a reality that they have either consciously or subconsciously prevented themselves from seeing. The vast majority of people are not emotionally mature enough to be able to handle this without eliciting a visceral rejection of any idea that makes them feel that way.

To a large degree, this is why I don't bother discussing politics with people anymore. I love thinking about and discussing the topic and all the fundamental philosophical and moral questions that go into it. But it's nearly impossible to discuss with the vast majority of people without mortally offending them. I've probably lost more friends over politics than any other thing in my life, despite the fact I hold no extreme positions on any topic, and generally frame discussions with questions rather than statements, using data to analyze popular viewpoints.