Given that scenario, "taking a walk alone down a dark alley in a city at night where a rough looking person in a hoody is approaching you from the opposite direction with their hands in their pockets" the race of the person should not, realistically, play a significant factor in determining the level of threat they present, as compared to the other factors. The bigoted assumption drawn from the made up statistic that the person is a member of "the race that is responsible for 90% of the homicides in that city" is that members of that race, categorically, are significantly more violent than members of other races. Otherwise, it and the statistic wouldn't be worth mentioning.
However, if this were a reasonable assumption to make about members of a race, then the other factors should not be relevant. "Taking a walk down Main Street on a Sunday afternoon when a finely dressed gentleman who happens to be a member of the race that is responsible for 90% of the homicides in that city" would be a far more dangerous scenario to find oneself in than a "rough looking person in a hoody approaching you from the opposite direction with their hands in their pockets who happens to be your own race, in a darkly lit alley."
Within the contrived scenario presented, the stereotype is irrelevant. Outside that scenario, it's absurd.
And.. no one is talking about seeing everyone as an equal threat, or no one as a threat, that's a weird non-sequitur you're projecting onto my comment. Likewise, not being paranoid about certain races will not inevitably get you killed and prevent you from breeding.
What I am claiming is that the stereotype you're trying to justify here as a valid survival mechanism is not.