It's not that surprising that the presence of a diverse mix of people makes it likely for imaginary people to be less stereotyped. I must admit as a non-native

It's not that surprising that the presence of a diverse mix of people makes it likely for imaginary people to be less stereotyped. I must admit as a non-native speaker, I am still not quite sure how to properly use "they". I wasn't aware of the possibility before this discussion occurred.