OK, racism. Kudos for grappling.
Now, I happen to live in an enormously diverse place. I don't expect people I see out in public to look, act or talk like me. You might hear just any kind of language spoken and may very well have no inkling what language it is, what part of the world it originates from. Berkeley, CA.
I moved into my house when there were 5 other people living here. One was black. Everyone in the house but myself and the woman here were from Grand Rapids, MI, including the black guy. The circle of friends from Grand Rapids had been in high school together, I believe. There were a couple of those who had lived here before I moved in, and with the others still in the house, were in a local band that played around this area a lot. They would practice in the living room.
Since that time maybe 70 other people moved in and out of the house. None of them were black IIRC. We chose our roommates, sort of, although the process was never organized or codified. It just happened that no other blacks moved in. Almost all were white. There was an Asian, maybe a Eurasian.
I fully believe that we're all the same beyond some minor physical differences between the races. There's nothing about the physical differences that should add any fuel to any segregationist philosophies. Nothing.
Years passed, people moved out, others moved in... many small rooms here! We did not share food, at least not officially. Rent was exceptionally low per person for this area.
TBH, I feared if a black person moved in, what might happen. It's not something I ever talked about when we got new roommates, which we did sometimes by conferring and choosing. I don't recall black people answering ads. However, I thought about it and thought they'd likely bring other black people in here and maybe we and our property wouldn't be safe. There's more crime in the black community. Is that a racist attitude? Maybe. It's not because of anything intrinsic in being black, it's just part of the cultural milieu of black culture in America presently, (even in Berkeley) at least in a lot of places. All this was over 20 years ago, before I bought the house.
Right now it's just me in the house, so it's not an issue, that is, who my roommates are. Would I consider personal relationships with people of a different race? Sure. But owning the house, I have infinitely more control than when I shared the house with people who were largely strangers. A house shared by strangers has a strange dynamic. If you knew your housemates before moving in with them it's one thing, but if you didn't it's something else entirely.
Edit: Arguably, everyone's a racist...