When liberals talk about “diversity” they mean diversity of skin color, not diversity of opinions.
A group consisting of a white liberal, a black liberal, a Hispanic liberal, a heterosexual liberal, a homosexual liberal, a lesbian liberal, a trans-sex liberal, and maybe a white conservative would be considered diverse to most liberals.
Ehh ... not until the white conservative was cast out from the group. Plus, they would keep a close eye on that not-to-be-trusted heterosexual freak ...