Here was interesting perception survey of what the other part thinks the other party believes
https://heterodoxacademy.org/social-...erception-gap/
In the survey democrats were asked questions such as "How many republicans believe racism is a problem still in the US today?" Democrats perceived about 50% of republicans believed that but when republicans were asked it was actually 79% of republicans believed racism is still a problem. When republicans were asked if democrats believe police are bad people, republicans estimated 50% but democrats answered 15%. The results also showed college educated people on both parties were more likely to be off on their perceptions of the other party than their high school educated or drop out peers. It was particularly bad for post graduate degree democrats they were 3 x more likely to be off on their perceptions of republicans than a democrat that has dropped out of high school.
My guess is that when we perceive republicans as not caring about racism or view democrats as antipolice we are most likely incorporating our own bias or are more likely to be on the "wing" of the party.