Adaptation Displacement: The film is based on a novel by Laura Z. Hobson, but most know only about the Best Picture-winning film.
Anvilicious: The movie's message has two components: one, anti-Semitism (and prejudice in general) is wrong; and two, that it's no good to believe that and not do anything about it. Yeah, the film comes off as heavy-handed, but in 1947, it needed saying.
Fan-Preferred Couple: A lot of modern viewers wish that Phil had chosen the bolder, snappier Anne rather than have a literally last-minute reconciliation with Kathy, who they find more of a typical love interest, but blander than Anne, who, unlike Kathy, consistently supported Phil even when she believed him to be Jewish and was willing to call out Kathy's hypocrisy.
Values Resonance: Though all of the themes on race are a bit Anvilicious in the film, the multitude of messages — racism in its different forms, its effect on children, its detriments to finding jobs and housing, its effects on family dynamics during marriage, and its appearance in different social dynamics, and society's shortcomings in fighting it — is still extremely relevant today.
Why Would Anyone Take Him Back?: Let's be honest: even though she learned her lesson at the end, Kathy was pretty consistently awful about Phil's project the whole way through. Contrast Anne, who supported him all the way through even after she found out he wasn't really Jewish but still wanted to marry him anyway; something that even Kathy failed to do when she briefly believed he wasn't Christian like her.