because it leads to excess competition. in the ecological sense, diversity stabilises an environment because of the various niches therein; when one species goes extinct, you better hope theres another to fill its void otherwise it leads to ecological collapse. it doesnt work in the case of humans, because we control the environment we create. in our case it leads to culture clash and with it, internal societal strife which is uneccessary; homogenous communities are stronger than heterogenous ones. faggot.
New Zealand