Her bias is known as "the outgroup homogeneity effect".
Outgroup homogeneity is the inclination for individuals to see ingroup individuals as more differing than outgroup individuals. The Outgroup Homogeneity Effect is the propensity to see an outgroup as homogenous, or as "all the same," while the ingroup is viewed as more heterogeneous or differed.
The society is defined by the human groups that are large in numbers and they are characterized by the independent and the dependent groups of people and the society grows and progresses is a sustainable fashion and owes its contribution to the aggregate collection of people that belongs to different sects and values and beliefs and systems.