(I guess I'm supposed to put this here?)

I think at least part of it is the tribalizing instinct. It's a fairly common mentality that you can find in almost any group. You see it in religion, in sports, in politics, in gender politics, in race politics, in certain lifestyles, hobbies, and so on. The "we good; they bad," mentality reinforces pack bonds, increases self-esteem, and gives group members something intellectually non-taxing and emotionally satisfying to bond over. This behavior is so deeply ingrained, we even see it in other primates, especially our closest relatives- chimpanzees.

It is mentally and emotionally easier to stereotype and strawman the opposition rather than view them as having equally complex, nuanced reasons for thinking the way they do.

As someone who strives to look at things objectively, here is what I see:

I see some redpillers who are lonely, desperate, and lacking in self-esteem. Many of them feel persecuted and shamed for being men. They're tired of feeling henpecked or like they should feel bad about being who they are. Some of them have been hurt by women and thus have come to see women as the enemy yet they still have the instinct to want to be with women. This brings them into a steep conflict they reconcile by joining places like RP, Incel, MGTOW, and so on. What they are really doing is seeking out emotional support systems to compensate for their (either perceive or actual) lack of emotional support elsewhere.

Some of these people lack the self-awareness to realize that they may be attracting only terrible women who hurt them because water seeks its own level. It's easier to blame the entire female gender than have to admit you need to work on your crappy cheese grater personality. Some of them don't realize that they are going to necessarily attract certain offenses from the opposite gender by virtue of the fact that they are men. Men are more likely to be the victim of manipulative gold diggers the same way women are more likely to be the victims of sexual harassment- like it or not, such behaviors are driven by deeply rooted biological imperatives. But they don't see that so they assume all women are manipulative, gold-digging whores with the mental aptitude of children. (I'm not saying all men or women are necessarily beholden to said biological imperatives, just that they inform a significant chunk of our species's behavior. Like it or not, that is a fact and we don't do ourselves any favors by trying to pretend otherwise.)

Anyway, I'm treading into TL;DR territory here. I'll try to sum up. Basically, we have a slew of men, many of whom feel angry, bitter, resentment towards women for various, individual reasons. They are, like many people in many groups (yes, we do it too) tribalizing as a way of bonding, validation-seeking, building self-esteem, and garnering emotional support. Unfortunately, this often takes the form of misogyny where they feel the need to assert that women are, in aggregate, inferior, ignorant, stupid children who need to be tamed or used like sentient fleshlights. Some of them fall into the trap of seeing women as walking manifestations of their SMV and nothing more. This can, obviously, lead to problems in how they regard women.

That's my two cents.... okay... maybe a little more than two cents. ;)