I am a motorist. I think I am an ok sort of person, most of the time.
The Personal Construct Psychology perspective suggests that
People develop constructs as internal ideas of reality in order to
understand the world around them. They are based on our
interpretations of our observations and experiences. Every construct
is bipolar, specifying how two things are similar to each other (lying
on the same pole) and different from a third thing.
So maybe the problem is that we have too many socio-psychologists (*) out on the streets looking for tribal warfare where it may not exist.
I suspect that when we are motorists much of the feeling towards unprotected road users comes from our own fear, perhaps subliminal fear, that we are not totally in control of our machine, and we are afraid of hurting other people. It is human nature to externalise those fears, creating a fictional "other", rather than admitting and embracing our own inadequacies.
Much the same is true when we are riding bikes. I often have to deal with people complaining about dangerous pedestrians being a threat to people on bikes. The standard response "have you considered cycle training" is not always well received.
(* should that be "psycho-sociologists")