Something that stood out for me was the African American segment. The only descriptive words in the narration were that they were Americans, and that "there are many different types of Americans", a phrase used throughout the movie. Not once did they say black, negro etc., it being obvious. However, they could easily have spoken of them as having a different label. It's a small thing, but it was pleasantly surprising.
I don't think they mentioned Fredric March's family being Italian either, but they certainly portrayed them with the typical overblown stereotype of the time period. The Italian stereotype in early movies are cartoonish to put it mildly, and cringe inducing. They were either organ grinders, or had 15 children. I have to remind myself that the influx of immigrants in the early 20th century may have made it easy to stereotype all of them. Many adults hadn't learned English yet, and this made it difficult to meld with other communities. This did not however, give movie makers the right to look down on Italians and treat them as having childlike minds. 🙄