Actually Ann's reply is easy to understand. Deutsch implies that a community like she was talking about would be intolerant. She replied by pointing out the mega-churches she lectures at, where the audience is very diverse and interracial couples are nothing special and are fully part of the community, Ann contrasted that with interracial couples among liberals, where the couple gives off vibes of 'proving something' by the fact that they are of mixed raced. She exemplified this by appealing to the common culture, to a Seinfeld episode, to prove her point.
In short she was arguing from examples that Christian societies are more harmonious and tolerant than our current culture.
She probably was trying to say what you said she was saying. But she should’ve said what you said. :-)
That’s true. Whenever I go to a large gathering of Christians, I see all manner of ethnic groups represented and all loving each other and having a great time! Ann is right.