I believe the reviewers were so hard on this tale is that they were unfamiliar with a smart young man who came from poverty but could fit in genteel society. Bryce Dallas Howard, in a beautiful portrail, was a woman who socially could run away without being disinherited. Not many people today can relate to this, but the topic was real enough in the 1920s.
This is a fine movie with fine actors and dialogue, a view of an earlier world. Don't let some critic whose view of the world started with the 60s talk you out of seeing a good drama, a piece of theater on the screen.