Um, the hours of a man's work has less to do with his learning in his spare time as to the man's drive to learn.
Just because he has full-time learning ability does not mean he has learning quality.
Feigy, where exactly is your source that suddenly all male jobs suddenly have killer hours, as opposed to the past? That would mean the wife, who is often working the same job as a man, will never be able to be there for her children.
Support a family on a 40 week job "once"? Yeah, also because people lived MUCH simpler lives. They never spent money, really. My grandmother and grandfather came to this country after the war and had factory jobs, raised their children, then had plenty for their retirement, because they never spent money. Like, never.
My father is a partner in a firm and at certain times of year has to work Sundays, but he is probably the most learned man I ever came across. He regularly flummoxes the rabbi. My dates even comment on his knowledge, and some of them were learners at some point. "Learned" does not equal "learning."
It is an incredible burden on a woman to take on child care and family support. If a girl chooses to do so, it better be with open eyes and an ability to take on so much. I know myself. I can't.
But I choose, bezras Hashem, that I can be a stay at home mother like my mother was able to raise me. She was able to be my mother free of guilt, stress, or worry. And she's a worrier. I want my children to have that same experience.
The conversation about sitting and learning has nothing to do with so-called modern working hours; there are many different types of jobs out there. If a wife says she cannot handle it, by the binds of the kesubah the man MUST go to work. And there are men, who are told by their exhausted wives that they cannot do it anymore, and the man just refuses to get a job.