Do the cons outweigh the pros of a multicultural and multi-religious society?

The first pro I can think of for a multicultural and multi-religious society is diversity. It’s good for society to have diversity. It would be boring if we were all the same. But then the cons of a multicultural and multi-religious society immediately spring to mind. Racial violence, ghettos, mistrust between the races etc. Humans seem hardwired to be suspicious of people who look different and believe in different gods so as long as this hardwiring is present, a multicultural and multi-religious society will never work. What do you think?