As early as in the first few minutes of the film, Pat speaks to President Lanford (a woman) about the speech the latter is going to deliver. The whole film has very much diversity, both in terms of women and people of color.

This suggests two things:

a.) We've really progressed from 1996, when a blockbuster of this nature could afford only one minority protagonist (Will Smith).

b.) The fact that this film is so campy (not to say, er, effing terrible), and yet has excellent diversity, shows that the two things have no correlation to each other. A film can have only characters of one gender/ethnicity/sexual orientation and still be utterly excellent, or it can be complete drivel and yet have a very diverse cast. Diversity in general film representation is important for a whole bunch of reasons, but it has no bearing on a film's individual quality.

Is that conversation the only qualifying conversation in the film?
I can't think of another...

The doctor talks with nurses about evacuating the hospital and with a patient.

This movie passes because of a scene right at the start of the film, where the President has a very brief conversation with the ex-President's daughter. She says something along the lines of 'Nice speech, Tricia' to which the other replies 'Thank you Madam President'. Both characters are named, and they're not talking about a man. That being said, this is the ONLY line in the movie that produces a pass, so it's not exactly resounding.