For those who suspect there is something deeper at work here than is ever suggested even by conspiracy theorists, well, I think so too. Just as food for your own thought and in greatly simplified form, here's the theory I've been working on....

Normies are normies because of the way they think. That is, they have a different way of processing the world than you suppose. Whether you agree with them on any particular point is not relevant, it's how you got there.

Primarily, they believe what they are told to believe by those they consider in authority. Did you ever notice that many normies are just out of touch with straightforward elements of reality? This is the reason.

This disconnection from reality is the main feature of what is called "psychosis":

Psychosis is a condition of the mind that results in difficulties determining what is real and what is not real.

They go on to say it's something wrong with your brain or whatever, but this is a misunderstanding (which may be intentional at the highest levels). But how do we get from there to what we see in the OP? It's another aspect which is misunderstood by the mainstream, but they do know it exists and we find the strong link described under "homicidal ideation":

Homicidal ideation is not a disease itself, but may result from other illnesses such as delirium and psychosis. Psychosis, which accounts for 89% of admissions with homicidal ideation in one US study....

So to recap, these people have a totally different mode of thinking leading to what appears as psychosis, which then easily spills over to homicidal thoughts about those they have been told to hate and who are the cause of their troubles.

I don't even know why I'm writing this because everyone seems a lot more content with, "These people are dumb assholes." Hey, but who knows who might stumble on this?