I am very unqualified to really pass comment on this as I do not know the area and the type of life, people of all sexes had in that era.
I do feel that normally most stereotypes are based on some degree of reality.That can either be played up or down depending on the purpose.
I suspect as Proulx is such a keen observer of human nature in all its frailties it is probably a fairly accurate depiction.
It seems for the most part, hard lives endured by people who in turn became hardened by the life itself. The exception is Newsome, who appears affectionate at the birth of his Grandson, but he lives a far less austere life. So perhaps it is easier for him.
Certainly he is strict as well, and obviously master of the "clan" as witness the thanksgiving scene.I can imagine him being affectionate with his daughter, oddly, I cannot imagine him being affectionate with his wife.
I think masculinity is defined by the poverty of the poor farmer life. Monroe is softer, but I think he can allow himself to be. He is not wealthy by any means, but he is not hardened by a life of abject poverty.
The big surprise to me is always Jack. He has to have endured a fiendishly hard and poverty stricken childhood, yet is the very antithesis of his father. Not only affectionate, but also full of hope. A quality, which most of the other characters do not seem to possess in any great abundance.
So perhaps masculinity in its many forms, is partly defined by circumstance, but also partly by the nature of the man himself. I am sure most of us can think of someone, who no matter how many times they are knocked down by life, will still pick themselves up and continue. Another in the same circumstances may grow bitter and twisted, no pun intended.
It has always interested me that Ennis, goes and immediately picks a fight when Alma has challenged him in the Jack nasty scene. He also fights with Jack, whenever it seems his emotions overwhelm him. Rough, terse and fighting, seem to be the defining qualities of men of that time and place.
Hey feel free to disagree though. I am female, and a Brit so my thoughts are mere conjecture !!!!