Throughout my time here I've interacted with a wealth of different people, with different views on things; people of different religions, different politics, different standards of evidence, etc, etc. There are some people who are very similar to me, with very similar beliefs, and only a very minute difference in ideology separates us. Similarly, there are people who are quite literally the opposite of me, and they have one or two things that we might agree on. However, there is one thing that I think dictates the biggest difference in how people think. This is a question of epistemology rather than one of ideology, which is to say, how we process and comprehend information is fundamentally opposed, separate.
I think the clearest example of this would be Individualistic versus Systemic thinking. This isn't just in regards to things like racism and sexism, which are two of the most obvious examples of such differences in thinking, it also affects something as simple as how we understand definitions. I'll go into an example of something which highlights this contrast in knowledge with one of the more obscure instances of this thinking. Election! Not the actual act of electing officials, though it is influenced by this thinking, I'm specifically referring to how we view elected officials. The individualistic minded among us would view each politician as uniquely responsible for each bill they pass, disavow, or even ignore. Whereas systematically minded people would think that a particular bill being passed is more or less due to a system of people.
Let's do a classic one, Trump versus Biden. The more conservatively minded will typically disavow Biden at every turn, take any excuse to rip into him. Conversely, they will typically defend or uphold Trump, even with apparent lies by Trump, but to get to the heart of the matter - the most typically defended point of Trump is that he was good for the economy (less so after Covid). Whereas most left-minded people would see that as a product of Obama's pre-established laws. What I'm trying to point out is that individualists typically care more about what a person has achieved, and more systemic-minded people typically care more about how something has been achieved. This explains why most conservatives find Biden so unfit to hold office. In their minds, Biden already had his chance and achieved nothing, and now he's stumbling over his words.
With this understanding let's take a look at the case of systemic racism and sexism, starting with sexism just to separate ourselves from more controversial topics at first. I typically see people arguing along these lines, "Sexism was abolished, females have the same rights as you and I," then the Systemicist might respond, "There are several ways that females are still disadvantaged by the society around them". If my theory holds up, then the first response should be based on achievement, which it is, they point out that there are laws in place that make females legally equal to men. But... on first look, the Systemicist doesn't really care about how achievement was made, but how it hasn't been made. You see, just as Individualists care about what an individual hasn't accomplished, Systemicist care about how the system hasn't accomplished.
It is a very thin line, and it can cross just like that. This isn't just a party line, sometimes liberals argue individualistically and sometimes conservatives argue systematically. For example; Cancel culture and freedom of speech. More liberal-minded people who would cancel an individual are specifically worried about what that person has accomplished and typically less concerned about how that person affects others. Conversely, Conservatives think that free speech should always be allowed because of how it accomplishes freedom. It's not exactly intuitive, because some liberals do care about how it affects things, and some conservatives do care that that individual person is being "repressed." I'm just giving an example of when the terms can be switched.
Ultimately the divide is means versus ends. One side cares about how something is accomplished, whereas the other cares about something being accomplished.