Streep on her performance: "I didn't feel I was living it"
In a refreshing moment of candor, Streep does name this picture as an instance where – in spite of the accolades – she isn’t too pleased with her own performance: https://youtu.be/eWjUYCf3yuM
But a large part of the “culprit” – it’s still an interesting film! – is the concept which makes both of her characters very stylized. And the entire then-contemporary story, regrettably, is vastly underdeveloped; we learn practically nil about these characters.
I think the movie (and the performance) works best at the beginning, this very romantic, psychologically and socially conflicted premise. The following tribulations don’t really manage to hold my interest.