Premise: Diversity is good. Diversity means diversity of ideas. Ergo, you will disagree vehemently with people, and this is a good thing under the framework of diversity. Do not confuse disagreeing with someone as that person being morally sub-human, and if you are able to do this your life will be more pleasant. Disagreement is a good thing, it is society’s mechanism for decision making in complex circumstances.
No.
Diversity has benefits and costs - it is neither good nor bad.
People, or groups of people in a democracy, need to decide what level of diversity they would like to pursue.
Personally, as someone who can live anywhere, I've chosen (and continue to choose) a very diverse place (the United States - specifically California).
I like living with people who invent jazz music and snowboarding and the Internet and I am willing to pay costs like some decreased degree of social cohesion and trust.
Other people, or groups, might have a different cost/benefit analysis and that is not wrong - nor is it wrong to pursue those aims democratically.