Diversity through quotas or hiring preferences to X, Y, Z classes of people are bound to make people angry.
Diversity though increased access to education, recruitment efforts, and accommodation of different strengths and weaknesses, personalities, work styles, management styles, etc. would make people much happier.
No. Maybe we just believe in equality for all regardless of race or sex. If a cool course opens but only for women, or people of color, of course that makes us feel alienated.