Kozaites, The Outcasts in Blade Runner

In 'Blade Runner', version notwithstanding, the outcasts are not just the replicants as one might initially assume. It could very well be construed that the majority of the characters in the film are the outcasts considering that they cannot live on the off world. Thereby, they can all be seen as imprisoned in 2019 Los Angeles with Tyrell as their warden.
In any case, the replicants are the outcasts of the outcasts in the movie. It is then important to ask why the replicants are the outcasts- because they are not human. But as W.A. Senior discusses in "Blade Runner and the Cyberpunk Visions of Humanity" the replicants display all the traits of humanity: fight for survival, compassion for loved ones, and other emotions. In fact, the relpicants are almost super versions of humans. This is why they are hunted, and considered the outcasts, because there are so few of them, yet they are so powerful.
Having these killer replicants on earth would surely scare Tyrell, who having sway over the police department, has them declared illegal.